Perfectly put, mackerella - I was going to say similar, but not nearly as well!
Nobody votes for whom they hate; it's just that, if you aren't anybody's preference, you won't get any of their points, which will go to people/songs who were (or at least whom they believe) were better than you/yours.
Another thing that I don't think we in the UK take seriously enough is that, for much of Europe, Eurovision is year-round. Many of the artists are top performing/recording artists in their countries, known and (often) loved throughout Europe.
Long gone are the days of not first hearing the songs until the actual contest, as they tour them around Europe (or at least give them loads of online exposure) for months beforehand. That's why it's possible for some of the 'growers' to do well on the night - they've already had months to grow in people's recollections and become earworms that they've already been humming and singing in the shower for ages.
What do the vast majority of us in the UK think in relation to Eurovision? We don't even have a big televised contest to choose the song (or presentation of the entry song, if judges have said "Yep, that'll do" chosen it independently) any more. We first start to think about EV once May rolls around and think we can just turn up, wing it and then get surprised and upset when we don't do as well as those who have planned, prepared, practised and promoted solidly throughout the whole year.
Most of Europe consider it a great honour to be chosen for EV, whereas we consider it a bit of an embarrassment - or at best, a bit of a laugh. And it shows.
We wouldn't enter the Olympics by sending a plump 60yo chap from down the pub who reckoned at short notice that he could probably give it a bit of a go - and then cry foul, unfair, everybody hates us, when Usain Bolt crosses the finishing line before our Trevor has even got going.