Love this post... having worked retail for over 15 years, I too know the stories. Working in a bicycle shop, the business is very seasonal. Spring is CRAZY time! My opinion has always been to suck it up and help the customer as well as possible, HOWEVER my famous quote at the shop is "it's just a bike shop..." Its all about an enjoyable, recreational experience, let's not make this too serious. (Similar to our model hobby) Nobody's living or dying, losing a job, missing a flight while on vacation, or anything like that. I have reminded customers of that fact also... shuts them up pretty quick too. For years, I have been the guy that the "good customers" come in to see, probably because I give them the respect they return towards me. I also slide discounts to many of them, even though they don't expect or ask for it. That's why I do it, they are the ones who deserve them, not the guy I see once a year who comes in for the big sale or wants us to price match internet pricing. 'Nuff of that.
Moving forward...I am in the midst of starting my own hobby/model shop and will be dealing with the same retail woes on my own. I'm sure it will draw all types, the nice thing being "I" get to call the shots. Tell the jerks "no", give the good guys breaks, and I'm sure "suck it up" once in awhile, go on, and remind myself... you reap what you sow...