Why is iTunes so heavy in Windows?

I really don't think they do it on purpose... with that strategy they would lose customers instead of gain customers.. and it's likely due to the way Windows works.. however it maybe be a hardware issue for you such as lack of memory. I don't know try rebooting your p.c. and running iTunes by its self and see how much of a resource hog it is... iTunes takes uses about 50,000 K of memory on my computer...