They're not real football fans. If you believe you can just decide to change your team on a whim like that then there's no point in being a supporter. Your team is your team. Changing it it like changing your parents, you're born to them and your team (or pick your team, you don't necessarily have to be local etc), but once you've got your team that's it. Yes, there are rare occasions someone might need to disown their family and then find someone else to fill that role but that's after you've suffered serious abuse at their hands or something similar. Soccer Club United of Manchester fans ditching their team to support a new one is like disowning your parents because they didn't get you the right trainers for Christmas. They're a bunch of shit house turncoats that have managed to convince themselves that they're something special when they're anything but.