I don't think there is anything particularly abnormal about it. There are people on forums across the internet learning how to make better cookies, fly kites, or blacksmithing. There are people who collect stamps, pocket knives, pipes, and just about anything else you can think of. Surely keyboards are no stranger a thing to collect than those. Keyboards aren't my one and only hobby. In fact, I am attracted to learning about almost anything made to the highest quality standards.
There are many every day objects that I use, and when my eyes are opened to the fact that the things I use don't have to be cheap crap, I usually want to learn about what I'm missing. When I learn about what I'm missing, I discover more and more about whatever I'm researching, and eventually a collection starts to build itself. I think it is a very natural part of human nature.