There is no allegiance for players to stay at any one club like they did in the 'old' days. When more money is flashed at you how can you not go for it. Their careers are short so you go for what you can get. It's all big business and it's hard to follow one team any more because of this.
I've been a Newcastle fan from way back when (Jackie Milburn-anyone). Watching this past season, I must say I was rooting for Sunderland (the horrors) as they seemed to give more to the game than Newcastle.