A few posters appear to have got decent cheap deals albeit with ridiculously early flights from obscure airports, and ultimately more time spent in a car or train than the actual flight to Seville.
For me, it's not necessarily the cost so much as the hassle involved.
The best example was the official day trip to Bruges last season which was both expensive and brilliant in terms of getting home before midnight.(from memory it was an early kick off)
In contrast I knew people who had got to Bruges for half the price before seemingly spending most of their saving in Burger King or overpriced airport lager, and not getting home until the following evening.
Ultimately not much different in terms of price