IF a restaurant is legitimately requesting gratuities from customers, then they are exempt from the minimum wage, and they are underpaying their workers, in anticipation of the tips they're supposed to earn.
If you're not tipping at these places, you're hurting those workers who are definitely not making minimum wage.
You tip at fast food restaurants?
In OP's defense; Chipotle, Panera & Subway all ask for tips. I personally don't tip them.