Thing is, whether people like it or not, it's another example of how watching habits are slowly moving away from traditional television, onto the internet. Youtube has totally changed the landscape during this past decade.
The younger generation are watching less TV than ever before, they're all over on YT. And it'll continue to do so. There's less stuff worth watching on TV these days. Why settle for rigid TV structure with repetitive shows when you can choose to watch and follow something more of interest to you instead? There's something for everyone on there to keep entertained, and really these fan channels are just another example of a new form of 'entertainment' that would've never happened before on TV.
You can question whether they're quality or not, but they're drawing in the numbers, so they obviously do something right.
TV companies must know they're audiences are slowly decreasing as time goes on while Internet viewing increases. It's just part and parcel of the way things are now.