Based on my experiences as a moderator of a Eurovision fan group. This is the only exaggeration of the four I'm making.
Marco fans really don't cause any problems in the group I'm in - I mean that. I've counted 40 arguments about Loreen (Kaarija being a distant second at 21), but only two about Marco.
Based on my experiences as a moderator for a Eurovision fan group. Spanish fans tend to get really passionate about their selection - usually bashing the winner. Then they get mad when a non-Spaniard does it.
Based on my experiences as a moderator for a Eurovision fan group. It's a weird paradox - Loreen fans are the single worst fanbase I've had to deal with (and I'm saying this as a Tattoo fan). However, Loreen haters (which come from many different groups, mind you) are collectively worse than the fans (but only slightly).
