I like looking at tattoos on others, but wouldn't dream of getting one myself. Some folk look good with them, and wear them well. The tats on others don't seem quite so well thought-out.
As for me, I can't think of any design or lettering that I would want on my skin permanently. What if I really, really want something but decide, a few years down the line, that it doesn't quite do it for me in the way that it used to? For this reason, I prefer to display my proclivities with T-shirts. It's much easier to change a T-shirt than a tattoo. Having said that, I'm not even overly driven to advertise to the world through a T-shirt the kind of things I'm into, though I do own a few rather cool cat T-shirts
But seriously, if I'm really into something, I'll read about it, learn about it, and discuss it with others. For the most part, I don't feel the need to get the T-shirt or the tattoo, or even the button. This has probably saved me a lot of money over the years.
However, cat T-shirts are an exception to that. I'm just a sucker for kitties. Definitely no tattoos though.
Second possible exception. When, one day, I begin my RV'ing odyssey, I can see myself getting a few choice shirts from various places I pass through. I've seen plenty of "Where the Heck is Wall Drug?" bumper stickers, but I wonder if they make a T-shirt for that? Still, as before, no tats though!