Not often i order, so when it happens I don't mind tipping the guys well.
So like on a 22.5€ order we made the other day, I gave the guy 30€, told him to keep the change. 40-45 mins later, it rang on the door - the guy was back in the neighborhood, he gave us two cans of coke and homemade Tiramisu from the Italian restaurant we ordered from, and he refused to get paid for that. Nice dessert!
What comes around, goes around in my world :)