I worked as a bartender/server for 12 years. I always tip on takeout. Most of the people bagging your takeout food make $2.13 an hour unless the minimum wage for servers has changed. Servers are also required to "tip" 10 to 20% of their gross sales to runners and bartenders, so its a double screw to the person that put your to go food in the system if you do not tip that person. I typically tip 15% on to go food.