The page amount does seem very low, so it doesnt seem to be overflowing. Zero is right ..
The mount items are not bound on pickup so if they are not for your race or class you can still see them.
Or hmm . in your SS they are ..if (!(itemTemplate->AllowableClass & _player->getClassMask()) && itemTemplate->Bonding == BIND_WHEN_PICKED_UP && !_player->IsGameMaster())
so you must be having GM on ?_?
What core are you using?