Not everybody is drawing on their skin to impress someone.
This. My signs are rarely visible, even most t-shirts cover them, and I don't exactly go around flaunting them. It's a personal thing that tells something about me, for those who like to know. It's also a kind of joke about the perceived disjoint between those who have tattoos and those who work in education or research. That said, I've seen a surprising amount of ink in the teachers' lounges, and one of my most inked friends is an elementary school teacher; the university people seem more conservative than teachers in this sense, in my experience.
Some people might prefer an expensive suit or a fancy car to maintain a certain kind of image, and they don't seem to get the same kind of hate -- though that kind of image is usually associated with a status that attracts haters for other reasons.
It's pretty hard to go about your life not giving any kind of impression. If you avoid giving one at all, then chances are that others will come up with all kinds of false impressions.