Small clubs with great supporters
When speaking of sport, teams and their fans, you need to know that the reasons that put them together are quite unexpected. A real fan will not follow a team because they are known; they always win and don't make any mistakes. He or she will follow them because of a complex set of feelings and maybe take in count how they actually perform. That is why small clubs have their supporters, but besides that there is one more reason for that and you might just think it is disloyalty. One fan can support two teams, one on a national scale, that is small and not very known, that doesn't play in the premier league, but second or third, and one that is world known.
It is all about the game
At the end everything comes to the game and it is just a game, so people shouldn't take it to seriously and be judging of someone's choice. In England, the part of Europe that is known for football, the world's most famous team game, there are hundreds of teams. It is natural that everyone will follow and be a fan of their local one. For example people from Ashford, Surrey will follow their local team Ashford Town and be Tangerines (that is what the fans call themselves). But at the same time they might support Chelsea, Liverpool or even Arsenal because they also compete on a world scale.
Hull City is one of those smaller clubs, just because not everyone outside of Great Britain will know who they are, but they have a huge fanbase. The same situation is with Cardiff City and Swansea City, they are good clubs that are located in quite big cities, where they are the only club, so there are no other clubs to be a fan of. But the biggest fanbase out of the 'smaller clubs' have Ipswick Town, Newcastle United, Aston Villa and Everton.