Look, all you stringers out there should remember that A LOT of tennis players, whether recreational or pros, are serious OCD sufferers... (And I include myself in there, as a mild case!) Some people can be very particular about their stuff, they like it a certain way, and they see it as disrespectful when someone messes with their things without their permission.
You guys slap a sticker on somebody's racquet without a second thought, but some of your clients might view it as anything from a mild annoyance all the way to a justified cause to completely freak out.
Back in the days when I was taking my racquets to a shop, they used to put stickers on them every time. I always removed them right away, but it was a PITA anyway, as they were difficult to peel off cleanly and there was always some sticky residue left that could damage the paint over time.
So how about this: Instead of placing the sticker on the racquet, just give the customer the sticker separately, so that they can do whatever they want with it.
They can stick it on the racquet, they can keep it at home, or they can just throw it away.
It should be up to the customer.
After all, it's their racquet.
Wilson BLX ProStaff 90: 368g, 7pHL, SW=352. (Wilson NXT 49lb / Lux AluPower 45lb).