I usually tip about 20% (give or take a percent depending on the change) for table service.
But how much should I tip if after a meal delivered to the table, I order a meal to go and pick it up at the register (it's not brought to the table). For example, a tip on a $20 meal would be $4.00. How much should I tip for that same $20 meal plus another $20 meal to go picked up at the register? $4.00? $8.00? or somewhere in between?