When our business had a retail component, everyone and his brother asked for discounts. It was exhausting.
They claimed they or their spouse to be a senior, a single parent, a teacher, police officer, firefighter, in the armed forces, a veteran, a foster parent, disabled, on a limited budget, you-name-it.
My response to all was that our profit margin was already so slim that we charged much less than anyone else, and therefore we didn't offer discounts. Nor did we offer free shipping. (If you tell me where and how I can ship for free, I'll gladly do so. As it stands, UPS charges me for every single package.)
It's almost amusing how people sometimes quite forcefully demand discounts of others, but expect to be paid in full for their own work.
To answer your question,
@fuzzybuddy, since almost everyone now expects a discount, retailers who offer said discounts simply mark everything up by an additional 10% then discount them 10%. It's a mind game.