I'm not superstitious but I tend to add symbolism to almost everything in my life. I don't know if that actually counts.
Superstition is for children and religious people.
Normally I would brush aside such a silly comment since I know you're trying to be funny and all, but superstitious people, while the basis behind their beliefs may be false, may use superstition (especially in the form of astrology or religion) to provide a sense of comfort in their lives. I do the same thing with the heavily symbolic way I view my entire life - I wouldn't call it "superstitious" but sometimes people do seemingly illogical things because there is a value that helps benefit their lives in some way.
The history of superstition is interesting, actually. Animals can be superstitious too and oftentimes it is caused by random negative reinforcement. In the cases of many common superstitions, such as walking under a ladder or breaking a mirror causing bad luck, it's very likely that either of those things could hurt you or people nearby, so it's kind of logical why people would be superstitious about it. It may not necessarily cause bad luck but it does prevent someone from doing something potentially dangerous.
Other superstitions evolved from symbols, such as the black cat being associated with witchcraft and forbidden magic.
Today, while most superstitions may not be literally valuable, they can help people emotionally and even spiritually. Some are invalid and may indeed harm people but most superstitions are completely physically harmless. So it can appear pretty bigoted when you claim that individuals who are superstitious are comparable to children. It's also pretty condescending to compare religious folk to children as well, but that's another issue for another time.
I guess what can be taken here is that you probably shouldn't make sweeping condescending statements about people that you only have an understanding of the most fringe of individuals in the group, because even if it's a joke, it won't always be seen that way.
