Tattoos themselves are stupid. Doubly so if it's some media IP. "I put Batman on my body!" "Look at this image of Goku on my calf!" I can't think of many things I'd want to do less than that.
I would agree with this in regards to product logos like Mt. Dew, Doritos, etc. characters though are actually the very purpose of tattoos.
tattoos are supposed to tell a story, and represent an important part of your story. getting Goku or Batman tattooed on you is your choice and speaks to your character in your story.
personally I don't have any tattoos because I write my story differently, but in another timeline I'd probably have someone like Batman or Superman on me.
those two characters played an influential role in my character development growing up. I remember seeing the first superman movie with Christopher Reeves and instantly connecting with his "american boyscout" mentality.
I remember reading so many batman comics growing up too. his thirst for justice, not vengeance, even though he was fully justified to take it struck a chord.
emblazoning both of their emblems on me would represent who I am and mark an important piece of my character history.
as I said, I don't need their emblems written on my flesh for me to tell my story. their impact is deeply engraved on me without the ink. but others may want to take their story to their next step.
I say, good for them.