This is already the norm in quite a few places in England. They auto-generate a tip on the bill and if you want, you can request the tip to be removed after.
They should, but they instead taught the staff to demand why you don't want to. I refused in one place and was confronted with them demanding why I wasn't giving them one.
"Was there something wrong with my service? You know that the tip is shared between us and the kitchen...."
We had the shittiest service ever at Fogo de Chao and I tipped $20 on a $150 bill. The waiter actually followed us to the door questioning why the tip was low and insulting us.