In the States, which already had a large and diverse (some would say annoying) set of interactions which de facto required substantial tips (e.g., 15 to 20% of the purchase price), tips are now also requested (though not yet required) for food and/or drinks purchased at the counter. Hip cafes have long had tip jars (with no particular expectation that one uses them), and one is expected to tip the bartender at least a dollar for an alcoholic drink purchased, but the new thing is that anywhere with an iPad-based payment system also requests a percentage tip.
A lot of people are dismayed by this. I for one select “no tip” or “0%” or whatever the majority of the time. But the new “turning around the iPad” normal doesn’t bother me either; at worst it’s a small, progressive tax transferring money from easily-influenced (rule-following? introverted?) consumers making luxury food purchases to counter-service employees who probably need the money more.