It's alright if some of us are indifferent to others amongst us- if it's not your cup of tea, that's okay. What's disgusting is that some of us go out of our way to put others down. There's only one reason that I can think of to do this, and that is JEALOUSY. Why would I care if other people support and like a band that I don't, except for my own personal insecurities?
Does anybody notice that the biggest insults and hatred for local music comes from within the scene itself? Because people who don't give a damn can't be bothered to waste their time on us. Gossip and small talk are to be expected and I'd even go so far as to say that it can be somewhat healthy for the scene- assuming we are all considerate, understanding and rational (quite a big assumption there.) But to go out on a smear campaign against another band?
If I thought a band, (Astroninja, let's say) could be better in some way, I would let them know. If their music is not to my taste, then I wouldn't listen to it. But why would I go and insult them on a YouTube page? If I think they don't deserve to be popular, well, that's just my opinion- hundreds of fans across the world think differently.
PS: There is no such thing as "doesn't deserve to be popular." Everybody has to work hard at building relationships with an audience and sustaining their interest. If XYZ band can be popular without playing good music, why can't YOUR band be popular despite playing supposedly better music? It's because they're doing something right and you're not, and complaining about it isn't going to do you any favours.
Paul McCartney mentioned in an interview that he found it quite funny when Oasis said they'd be bigger than The Beatles, and his words to any band in the world that claims that is "Good luck, son." Yet we don't see him posting insulting comments on Oasis videos now, do we?
That's because he's got better things to do, has nothing to prove, and has his own music and career to worry about. As do the rest of us. Insulting other people in your field, whether you are a musician, athlete, artist, whatever- is a sign of incompetency, insecurity or inadequacy on your part. If you honestly don't feel they deserve the glory that they're getting from their own hard work, then go out and achieve greater success yourself. Because nobody thinks highly of armchair critics.