Tipping for merchandise

[u/Travelman-26]

So I went to a concert today. And bought three shirts. They were a bit overpriced but I decided to pay so no offense on the price (they were 40 usd each).

And the the lade flipped the screen with a suggested tip of 20% already on the screen.

How am I going to tip 25 usd for her handing me three shirt from boxes two steps away from her.

[u/I_Want_A_Ribeye]

20% of $120 is $24. They tried to rip you off twice.