When I was sixteen or so, I was a regular at CD Warehouse. They were one of the few that would let you listen to CDs before you bought them and they sold CDs for cheap because they were used. I went there any time I had money to burn on a new CD.

Some days I would go in there and find what I was looking for. But I was picky and $8 was not a small investment at the time. So some days I wouldn't buy anything. At one point I was going through a slump. I'd gone three or four visits without purchasing anything.

The man at the counter gave me some grief about it. He asked if I was ever going to buy these CDs that I'd been listening to. I told him that I would when I found a CD I liked. He told me to start demo-ing CDs I liked so that I would buy one. As it turned out, the two CDs that day were losers so I didn't buy.

But because of our conversation, I never shopped their again. Which is a shame for them because eventually I was making enough money that $8 was not such a huge investment. Eventually I'd reliably buy two or three CDs every visit. But not CD Warehouse, because I saw that they saw me as an undesirable customer.

The moral of the story is that you have to be really careful when you single out customers. Yesterday's grussly-haired teenager is today's young professional. Today's thrifty college student will tomorrow be using that college degree to make money that he can spend at your establishment.

You have to target abuse, but don't target people unless you really gotta.

I'm almost a year late on this, but Best Buy has apparently decided that targeting people is a good idea. They've even gone so far as to label people angels and devils, depending on whether their buying habits gain and lose customers:

Best Buy's angels are customers who boost profits at the consumer-electronics giant by snapping up high-definition televisions, portable electronics, and newly released DVDs without waiting for markdowns or rebates.

The devils are its worst customers. They buy products, apply for rebates, return the purchases, then buy them back at returned-merchandise discounts. They load up on "loss leaders," severely discounted merchandise designed to boost store traffic, then flip the goods at a profit on eBay. They slap down rock-bottom price quotes from Web sites and demand that Best Buy make good on its lowest-price pledge. "They can wreak enormous economic havoc," says Mr. Anderson.

Best Buy estimates that as many as 100 million of its 500 million customer visits each year are undesirable. And the 54-year-old chief executive wants to be rid of these customers.

Mr. Anderson's new approach upends what has long been standard practice for mass merchants. Most chains use their marketing budgets chiefly to maximize customer traffic, in the belief that more visitors will lift revenue and profit. Shunning customers -- unprofitable or not -- is rare and risky.

Risky indeed.

It is a bit ironic that they put all of these deals front and center in advertisements and then state that those that plan to hold them to their word are bad customers that they want to be rid of. Policies that are ripe for abuse (such as refund-flipping) ought to be tackled, for sure, but for the most part the loss leaders are simply those that are responding to the advertisements they put out. If it's costing you money, don't do it, but going after those customers that fail to fall for your bait-and-switch scheme by purchasing what you're advertising gives lie to the fact that it is, in fact, a bait-and-switch scheme.

But that's not the real problem I have with it all. The real problem, in my view, is that they are branding certain customers undesirable when those customers will not always be undesirable. Johnny Professional will not forget how he was treated when he was Johnny Student. All retailers use their customers for their wallets, but you don't have to be so danged obvious about it.

Almost as bad as they treat the devils will be how they treat the angels:

Staffers use quick interviews to pigeonhole shoppers. A customer who says his family has a regular "movie night," for example, is pegged a prime candidate for home-theater equipment. Shoppers with large families are steered toward larger appliances and time-saving products.

The company hopes to lure the Barrys and Jills by helping them save time with services like a "personal shopper" to help them hunt for unusual items, alert them to sales on preferred items, and coordinate service calls.

Best Buy's decade-old Westminster, Calif., store is one of 100 now using the new approach. It targets upper-income men with an array of pricey home-theater systems, and small-business owners with network servers, which connect office PCs, and technical help unavailable to other customers.

On Tuesdays, when new movie releases hit the shelves, blue-shirted sales clerks prowl the DVD aisles looking for promising candidates. The goal is to steer them into a back room that showcases $12,000 high-definition home-theater systems. Unlike the television sections at most Best Buy stores, the room has easy chairs, a leather couch, and a basket of popcorn to mimic the media rooms popular with home-theater fans.

So while the devils get shunned, the angels get annoyed. Besides price, one of the things I always appreciated about Best Buy over Circuit City is that their salespeople were not annoying. Circuit City had a commission-scheme for a while that made the salespeople get in your face while Best Buy help managed to be both helpful when you needed them and absent when you did not.

Even the process they have to sort people out seems annoying. Interviews? I don't like being asked questions about my buying habits. There's also the ambiguous tagging of folks by their behavior.

Some people look like they've got money and will be "good customers." Some people look like they don't and won't buy a whole lot. Disproportionately the first category are likely to be white and the second not-so-much. To suggest that this will not happen is putting an awful lot of faith in hourly help. They've actually gotten into a little trouble because of this before:

Earlier this year, Mr. Anderson apologized in writing to students at a Washington, D.C., school after employees at one store barred a group of black students while admitting a group of white students.

I'm not at all saying that Best Buy's leadership is responsible for that, but their new policies will lend itself to those kinds of errors being made.

Relatedly, I wrote a while back about Best Buy discontinuing rebates, a move that I applauded. I did not realize that this was all part of a larger scheme to abase, repell, and annoy. I'm still glad they did it, though.