I was asked to tip 3 times on a Pizza Hut carry out order of breadsticks.

I notice at my local Pizza Hut the only times upon pickup I get asked to sign a receipt, which asks for a tip, are the times I don’t leave a tip. Today was no different, but this took the cake. I ordered a single order of breadsticks for carry out so I opted for no tip. When I arrived to pick up my bread sticks the cashier verbally asked if I would like to leave a tip, I said no thank you, she then printed out a receipt to sign which asked for a tip, I put $0 as a tip, then she prompted me to confirm my order on the screen, which again, asked to leave a tip. I was asked to leave a tip 3 times in less than 30 seconds for a carry out order of $4 breadsticks.