That's what you think but the cost of remaking stuff is very high. For example I would need to sell 42 sets of the sill clips I have to recover my costs. As I started doing the clips for my own car I'm not too bothered. I guess I'll get there one day
Door strips and window rubbers would need tooling to be made and the cost of that is way out of my league. If someone does them don't expect the price to be less than someone selling new old stock