I'd say the stocking up was do to the jumping. I always wrap my pony after I jump her hard, especially after XC schooling. In a nice clean dry set of standing wraps with some menthol rubbing alcohol on her legs to prevent this sort of thing.
Jumping is hard on a horses legs, especially their back legs and then to go from a few hours of XC schooling to be getting stuffed back on to the trailer to go home where they're going to lean on the butt bar and back legs, the extra support of standing wraps has always just seemed like common sense to me.
My suggestion would be to leave your horse wrapped over night after hard jumping workouts in the future.
But I would like to throw in there make sure you are giving your horse a long enough walk afterwards, it might have been too short, we always take a nice little hack after our XC schooling around the grounds. Two hours really isn't a long trailer ride. And get some practice wrapping so you don't bandage bow your horse :)