The tipping thing has gotten completely out of hand. I had to select "no tip" at a freeking Dunkin Donuts drive through the other day... In my opinion, to-go, counter orders, or drive throughs should not pressure you to tip.
As for establishments with an automatic gratuity, my opinion is similar to what others have said here, for outstanding service, I will still occasionally add a bit to the standard, My standard tip for normal service is 20%, so if the mandatory tip is 15%, I'll add the other 5% for normal service, or even more for excellent service. If the server asks me to tip more than I already have, yeah, I'm unlikely to return there.
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