I like how there are many people saying "It's just a game, get over it" etc without realizing that being called a "random" is an occurrence mostly present on the forums rather than in-game.
@OP, as far as I've noticed, random is not an insult - it's just what veteran members of these forums use to refer to people who usually aren't very well known (in game or on the forums).
Despite the relatively harmless intentions, this word can lead others to think it means the following things: insignificant, without value, without rights to express ones' opinion etc. I've never seen this happen in other forums I've joined, and I personally find it distasteful (there is no reason to be hostile towards people who are trying to strengthen their bonds with the community, even if it is in a playful way). Then again, this is the internet so there is no reason to be offended or bothered by anything related to it.
I know I'm probably gonna get a lot of shit for expressing my view on things, but I suppose that is to be expected.