Several months ago had sick dog. Vet said blood disease, only seen a few times.
Medicine , he said. listed for $ 900 + , but if I find someone with a discount card, would cut it in half at WalMart
Went to WalMart, lady working there was friend, husband worked for me before he died..Told her I needed prescription for my dog. She took prescription and my borrowed card, came back and said was close to 425 dollars, but she thought she could   " work some magic " . Took paperwork to back and spoke with druggist, came back smiling, final bill was 40 something bucks. 

Heck of a mark-up somewhere.