I love Southwest Airlines. The low fares are great. The egalitarian boarding system is great — even after they implemented the new numbering system. Snacks and meals? No big deal. Airports have restaurants. The main things to me are a cheap seat, getting where I’m going on time with as little trouble as possible, and dealing with employees who give a damn about me and what I want.

That's why I was so disappointed with a recent change Southwest made to its beverage service.

I fly enough with Southwest and drink so little on planes that I usually have some coupons in my computer bag for that occasional glass (or two) of bourbon I'll tip back on a late-night flight home. But if I don't, I like to pay cash. It's easy. If I charge something, there are receipts to worry about, and I harbor this secret dread that something will be wrong with my credit card and the attendant will yell out in the cabin that I’ve been declined.

But if I'm buying drinks for a client on a flight, or if I've left all my cash in Las Vegas, the card is good, too.

Bottom line: I like choice. And Southwest has taken away one small sliver of it. Now, if I don't have coupons, I'm forced to swipe. In the words of the immortal poet David Spade, "me no likey."

Making matters worse, the explanation just doesn't feel right to me. In justifications published in news accounts as well as announced over cabin P.A. systems, the airline says it went to credit-only payment because customers wanted it.

Nonsense. Do some travelers want to pay by card? Of course they do. But it's hard to believe there were many travelers clamoring for the elimination of the cash option. Did a single flyer utter the words, "Please, don't let me pay by cash. Force me to use my card?" I doubt it. Once my current stack of coupons goes, I may never have another drink while I roam about the country. (I might not have anyway, since they stopped serving Maker's Mark. But that's another column for another kind of Web site.)

Here's the point for self-service deployers: Keep customer options open. And if you do shut an option down, level with the customer about why you’re doing it.

I would never shop at a grocery store that is self-serve check-out only. Sometimes I don't even know what kind of fruit my wife has tossed into the cart, let alone how much it costs. Sometimes a box is too big and I don't want to fuss with getting it out of the car before I get to my car. Sometimes I just get lonely, for heaven's sake, and like a cute cashier to ring me out!

But even worse, though, is when I want to use self-service and walk through a store with rows of self-service checkout stands sitting closed, red LEDs warning me away as though there were some latent danger lurking beneath the cold scanners and inside the folds of plastic bags. If you're going to deploy self-service, have enough of it available that the option is a meaningful one.

Same thing for hotels and others: If you're going to offer self-service, have enough of it for the option to be meaningful. And while we still shouldn't have to say this, make sure the kiosks are working.

Home Depot learned the choice lesson the hard way a couple of years ago, when the CEO oversaw a mammoth self-service deployment that overtook, rather than augment, the human side of the checkout process. Customer-service ratings fell. Sales dropped. And soon enough, the CEO was printing resumes, perhaps (one hopes) at a self-service copier somewhere.

Must customers have everything? No. They don't. Despite the gotta-have-it-all hype used to describe the modern consumer, truth is, most folks know there are limits to what stores — and airlines — can and cannot do. What is important, however, is to make available everything feasible. And if you're not going to do so, to fess up on why, and prepare for the consequences.