Anyone else notice when you use a Groupon at a place the employees are almost always snotty about it?

I love Groupon! For example, I got a Groupon for a set of acrylic nails and the whole time I was there the lady doing them was complaining about how the only people that come in are using the Groupon and she's not making enough money. I was going to leave her a good tip regardless of service but she made me feel guilty so I left her more than half of the price of the regular price service. I mean you chose to put your business on there , and people are supposed to still tip as usual.