People often ask me why I don't sell my stuff. I tell them that then it would work instead of a hobby. That would take the fun out of it.
It's the same with me and fixing PCs for people. I often do it because I enjoy fixing computers and working with them. I also like to show people how to keep them up to date and well maintained without spending a penny on software by using the best software that is free such as AVG, Spybot and ccleaner. They still give me a few bucks for my trouble and I don't want to upset them by saying no, but I would do it either way.