Michael Wilbon has a great article (from last week, before the punishment was announced) detailing why spying on other teams should carry a harsh penalty. I had a co-worker who was convinced that only serious conspiracy could have gotten the New England Patriots to the SuperBowl after the 2001-2002 season, so certainly the subsequent success has put the Patriots in a position where many love to hate them. And sure, post-dogfighting the league is trying to demonstrate that they are not just tough on players, they hold everyone to higher standards.
But, here's the thing. It's like speeding, everyone may do it but it doesn't stop making it wrong. So, if I get pulled over or caught by a speed camera I hate it. It annoys the crap out of me. But, I was speeding and I know that speeding carries risks, one of which is tickets.
Barry Bonds has faced all manner of ire for something no one has been able to prove he even did. Sure, speeding and taking illegal drugs are actually against the law, while my understanding of the spying that has taken place is that it may not violate any laws, but it clearly violates league policy. And when you work for the league, those are the rules.
So, is the punishment big? Yes. But, I think that's fair. Even if everyone else is doing it. I'm not trying to suggest that that's what you get for getting caught, but as people have pointed out. This is not one rogue team member. This is not one person doing something on their own time. This is clearly institutional behavior. So, the whole team gets to feel the brunt. And maybe other teams will think twice about enhancing their advantages.