tipping

So I have been experiencing this more and more lately. But this weekend I saw it everywhere. Why is it that every time you purchase something these days, the credit card reader or receipts are asking for a tip? I am all for tipping and over tip myself, but you have to be at least doing something...

How do you find yourself tipping at restaurants? I mean do you find yourself tipping the average 10%, or do you go over more or under? I know it really depends on the service with me such as how they fill your drinks, how nice they are to you etc. I do find myself over-tipping more than average...