I think you have this backwards. What would the bartender have to gain from doing this? If anything, he'd be hurting himself. Serve shitty drinks, tips go down. The owners would be the ones profiting.
If you order top shelf vodka, then you deserve what you get because it is basically the same, if you are ordering top shelf liquor in a mixed drink, you deserve it for being a poser tag who ruins good liquor, and it you order top shelf whiskey on the rocks and you can't taste the difference, then you sir are a fucking moron.
Seriously if you can't taste good whiskey you should probably turn in your man card and stick to wine spritzers. Seriously...
What is a poser tag?
Also what are your feelings on apple pucker?
Apple pucker tastes good.
But give me a bottle of crown and gtfo of my way until I start crying and I can't get up on my own.