It depends *a lot* on what the "suppliers" have to do for you. If you state you need certain level of security and privacy are necessary for that certain contract, obviously the suppliers that want to earn your contract will have to comply.
On the other hand, the wages to feed my family come from software development 100% for (and on) Windows (at work and at home too!)
I guess that you are a bit overly concerned about your privacy. It's your right and I won't judge you for that.
Others are not. And not necessarily because of laziness. The fact you don't see their reasons, it doesn't necessarily means there none.