my feelings on tips are that if the person providing the service is taking a healthy percentage or the full amount of what is charged then its unnecessary to tip, if you think of a waitress she gets paid a low hourly wage for what she does, if you tip her its a little that goes in her pocket for the service she provided outside of what she would get paid on her hourly wage. when it comes to tattoos the price is not set in stone and the artist can earn as much or as little as he/she likes by adjusting the price accordingly (within reason of course).

but hell what do i know, im a scrooge, i dont even like tipping the pizza guy when he rolls up in his mustang lol