Great Clips

This is the second time this has happened to me Mona the hair stylist has demanded a tip of $5.00 dollars when she has already charged me $18.00 for cut, I am not a Senior but the ticket says $16.00 senior cut, the first time this happened she took $20.00 and sed we are finished, I thought it was up to the customer to tip or not is it a law saying you have to tip. you need to check this woman out I was in the chair for about only five minutes and out, sound like she wonts. to make $1.00 a minute plus what great clips pays.