I don't necessarily think they go about cheating, but I don't think that every player is just so altruistic that they would never break the rules or would immediately ensure that if anything was wrong they'd run to tell the refs. We've had players pop hot for drugs, we've had players with off the field issues, etc. Sam is a fierce competitor, I think he'd do just about anything to win. I do think his line would be intentionally going out and attempting to cheat before a game started, I don't think he would run to the refs to inform them if he was getting a slight advantage over something like this.
Similar to when players always give themselves a favorable spot, it's technically cheating because you're trying to give yourself extra ground that you did not actually earn, yet there's not an outrage every game about players attempting it. Every team does it, so while not everyone is scheming to break rules, they'll all happily place the ball a little further than it is, and happily accept if the refs don't catch it. Just like if they get away with a hold, or a facemask or something similar, they'll happily let it go.
Now if the Patriots did in fact go and alter the footballs before the game that would be one thing, but if they just happened to benefit from it happening then that's another thing. Now reports are saying that only one ball was really deflated, 2 pounds under the minimum, the rest were just a few ticks under. So perhaps Brady likes lower pressure, which the temperature drop would certainly allow for a few ticks under the minimum. 2 pounds would be different, as there wouldn't be enough of a temperature change to cause that however. If the reports are true that it was in fact only 1 ball, then I would say it doesn't appear to be some big scheme.
I don't know, I just believe if there is very solid evidence or proof that the Patriots did in fact alter the footballs then that would be one thing, but right now I don't see any proof of that, and the evidence has been contradictory in some cases. Maybe it's all a big cover up, but at this point that remains to be seen.