In fairness, tattoos are a permanent representation of our rebellious stupid youth and even a lot of Christian metal bands have had such symbology surrounding them.

When we're young, we're stupid. When we're rebellious, we tend to rebel against a lot of things in our lives, which for a lot of kids of the past few decades has actually been Christianity establishment.

What I mean to say is, kids rebel against their authorities and Christianity is a major authority for a lot of people. Nothing is more rebellious than an upside down cross as a middle finger.

But a tattoo is forever (or massive scarring). Kids don't gain a concept of time until they're at least in their 20s and coming to terms with the fact that time moves forward faster than we think.