This is all due to confirmation bias.
There are certain people who, when they like something a lot, make it part of their identity. You'll know if they're like that just from being around them. (be it online or otherwise)
These people also tend to be annoying, because they don't have much an idea of who they are. They're not very mature.
These people that tend to be annoying appear to represent the entire fandom because they're more visible, since they only talk about these dumb things they like.
To anyone saying Blockland is a fandom, keep in mind that 1. we aren't feverishly discussing Blockland here, most of the discussion is in off-topic and 2. there are lots of people who don't like Badspot or the state of the game right now and they don't really get any kind of angry reaction