Zayne was really nice and chipper, and he said tipping was okay, so Bart paid for the coffee and then put some bills in the tip jar. He didn't really count how much, but he put nearly twenty in the tip jar. He didn't really get how tipping worked, but it felt a lot like sharing money, and that made him feel good, because sharing was nice, and he had more than he'd needed before Riken, and he felt like he had more than he needed now.
"You don't mind? When people come in and ask you to tell them what to drink? Because I know that's not your job, even though you do it really well."