Because people like nothing more than to judge others based on superficial things such as tattoos to uplift themselves and build up their ego. Especially old people.  It's like they have nothing better to do in life than to look down on other people to increase their already big enough ego. That's also exactly why people insult and swear at each other.  

Its exactly this ego building, which is the driving force behind most of the problems we have amongst each other nowadays and why some people just can't stand one another. Their egos are conflicting. Battling. Creating a repelling force that is pushing them far away from one another. The only outcome of such situation can be either splitting paths or battling it out until one gives up.

People need to learn to control themselves and  kill the ego, or at least realize when it's taking over common sense and be able to ignore it.  Because, only when not under the influence of the ego, is one able to react to a situation propperly. When they can't do it though, only negativity can come out. And that's why our world is so messed up today.  

Our ego is taking over and we can not control it so, we react irrationally and negatively.