I think when it comes right down to it, most of the NFL players are looking at money as one of the top factors of where they will play. I can hardly blame them when the difference is millions of dollars. I also think fans look at players as "hometown guys that love where they are playing and living." When in reality, the NFL is just a paycheck for a job they enjoy doing. Further, many players making that decision of switching teams, had no choice at the beginning of their NFL career, they had to go to the 1 team that drafted them. Sure, there are benefits that one City might have over another, but going to another team, another City, might actually be exciting and a new challenge for a player. Or even a way to get out of a City/Organization that they really weren't that fond of to begin with.
I can imagine that there are some ex NFL players wearing Super Bowl rings, that would probably gladly exchange them for a million or more dollars or whatever was comparable pay back when they got the measly check and ring for being a part of a SB winning team.