Boycotting won't fix anything. They have enough business cutomers to survive even if they lose all their consumer business. And willingness to spy sure helps get those government contracts.
On top of all that, AT&T isn't the problem. It's the government and sketchy laws they use for mass surveillance. They're the ones doing the spying. AT&T is just making it easier for them. So boycott the goverment - if that's even possible.
Not to mention that Google Apps copies Microsoft Office, and does the online component of that better than Microsoft. Really, the whole history of software is nothing but copying and improving on what someone else is doing.