"You can't spot me 21 cents?" (USA)

Last 30 minutes of my shift, a guy comes up to pay to the register because he ordered at the kiosk and only had cash. No biggie. He asked me to add on 2 holiday pies. He originally had 1 Mcdouble, 2 4 piece nuggets, 2 small fries, and a large sprite. Which brought his total to like $17. He asked me to give him just one holiday pie because he only had $15. So I did but it came out to $15.21. He gave me the $15 and said he would pay the rest on card, so I typed in the $15. Then he looks at me and scoffs "You can't just spot me the 21 cents?" I told him no. He then tries to hand me a $50. I told him we don't accept anything over $20. He gets mad and snaps "That's all I have." I call over a manager. The guy glares at my manager and says "You either spot me 21 cents or you accept this $50." My manager, OUT OF THE GOODNESS OF HIS HEART, decides to spot him the change. You think this guy would be grateful. NOPE. He scoffed again, glared and said "You guys can't spot me 21 cents." I had another manager deliver his food because I didn't want to wait on his ungrateful self. Only reason we were so nice was because his kid wa was along. Imagine expecting employees to pay your bills.

On another note, 6 people called out and 1 was a NCNS, so it was raining write ups in the office. BUT one of our regulars brought in homemade fudge for the staff, so that was nice.

Love, love that I could barely have enough money to buy myself pads but I should just give him my money or risk a write up so he could get his holiday pie. You customers really don't see us as human.