Also, there's a big difference between letting NSA protect US against Real Threats - real national security people-are-going-to-die threats, and spying not just on every single citizen on the planet (which includes corporate espionage), but on American citizens and companies, too.
Just like everyone has a little "evil" in them, without all of us being Hitler, the NSA can do a little bit of spying on important targets, without going 10/10 on the scale of evil spying.
So no, I really don't think "this is their job" or that "everyone knew they were doing this". I think the vast majority of people thought NSA would be reasonable with their spying.
I also hate it when people say, "didn't you see when they passed the Patriot Act? You should've expected this." Perhaps, but if you go back to when they passed it, they did it in literally hours, and if you watch Bush speak about it [1], he makes it sound as if they are only going to use it to spy on the terrorists' communications - not everyone's. Going by how fast they passed the bill, and how few details were offered, you can't really blame most people for "not knowing".
Heck, it was even called the "anti-terrorism bill" on TV, so I don't think people imagined that meant all of their communications are going to be swept up, because they were now thinking everyone is a potential terrorist (which is what "collecting it all" means) until proven otherwise by their systems.