I owned fly fishing and hunting stores for twenty five years, and there are alot of similarities with what you guys are talking about. Broken rods, leaky waders, gun cleaning and repair, special orders, "I want this tomorrow" etc.
I think a good retailer has to train alot of customers to be good customers. I would have three piece suit guys walk in with two filthy duck guns, that hadn't been cleaned in ages, and tell me they needed them tomorrow. No problem. Here is my "tomorrow price" (twice normal). Without exception, they paid it and were glad for the service as most gunsmiths in the area would laugh and tell them it would take two weeks and give them alot of attitude with it.
Retail is a two way street, and I've sent more than a few guys packing over the years. I used to love telling some a&$#*^e that I thought he should find another gun shop because I obviously wasn't making him happy. But alot of guys whose first visit was like your "I'll be back for it at 4" guy, turn into great customers who don't chisel you and bring you good referral customers.
Too many small businesses try to be liked by selling cheap shotgun shells, cheap parts, etc. The same guy that comes to your store for your low prices, will most times go to another in a minute if he finds a better price.
A contractor buddy of mine had a great line when he was bidding a custom home and the clients were beating him up on price. He'd say. "... there are three things, QUALITY, LOW PRICE and SERVICE. You can choose any two, but not all three."
Just my .02