Well, Google does read your email to show you better ads. But they never made a secret of that.
> The NSA can get what they want anyways.
If they really want to, yes. That doesn't mean one shouldn't try to make it as hard as possible for them. They won't bother if their cost/benefit analysis says you aren't worth it to get out the big guns. (Reliable 0 days aren't cheap and using them too often soon makes them worthless.)