In NSW and its flexi betting option, it is possible for a trifecta pool to be $10000 and the dividend to be say $160000. That is, if the pool of $10000 is reduced to $8000 after the take and the only correct trifecta combination was by a punter who had a flexi bet which gave him 5% of the dividend. That punter then has a ticket worth 5% of $160000 which is $8000.
A simplistic example but I think it answers the question.