With apologies to Count Von Count for the altered lyrics,
Discounting is wonderful,
Discounting is marvelous,
Discounting is the best thing to do.
Discounting is happiness,
Discounting is ecstasy,
I love a discount, don't you?
Well, don't you? Of course you do; we all do. Everyone loves a deal. Somewhere along the line it became expected in wine retail. Customers often get "rewarded" with 10-20% off when buying a case or more, but what happens if you need a bottle or two the following day? Maybe you can plead your case effectively. Maybe the clerk remembers you. Maybe not.
If you end up paying full retail for the second purchase were you really rewarded for the larger one or punished for the smaller? Personally, I would like to see retailers do away with these discounts entirely and let me buy what I need at a reasonable price. Wines can always be put on sale to drive larger purchases. If you buy 30 apples in a grocery store do you pay less for the apples than someone buying two?
At the other end of the scale, there is a wine shop in Portland, Oregon, bafflingly successful, that makes you purchase a lifetime membership in order to get discounts. Those discounts apply for loose bottle purchases as well as cases, but the concept alone forced me out the door. Never to return. Try this at a department store. In order to get these jeans for $35.99 instead of $49.99 you have to give them $100. I look at that and say to hell with you. Somehow Sam's Club exists though. I'm sure those foolish enough to join the club become extremely loyal since not shopping there means wasted money.
The discount mentality that pervades in wine retail is ridiculous and it galls me to no end when I need to buy a bottle or two. No retailer likes making less money, it is a capitalist enterprise after all. Markups in the wine world tend to the low side compared to other retail businesses but put a reasonable price on your bottles, explain the system and I believe people will repay you with loyalty.
Everyone likes to reward their best customers. If not with volume discounts, then how? Try special tastings for them; open something outstanding when they come into your store; give them a bottle now and again (where legal); make sure they get first shot at sought after releases, etc. Plenty of ways exist to consistently reward good, loyal customers without abusing everyone else.