I'd rather my dad leave it up rather than not putting it up and getting wee all over the seat, which he doesn't clean up. Then when my mum or I come to use it and complain, he says, 'deal with it'.
I've never seen an issue with who puts the seat up or down.I also live with just boys and couldn't give a t0ss whether they leave the seat up,at least they are not p1$$ing all over it for me to then sit on!