tip for service OR tip service
This morning, I browsed an English websites and found below sentence written by a netizen. I have a question regarding it:
In a forum, the net users are talking about whether or not tipping for delivery food. One user said "I tip good service, and don't tip bad service. I never feel obligated to tip." I think there should be a "for " after "tip", that is "tip for good service and don't tip for bad service", because "tip" should be followed directly by someone. Am I correct?