Definitely can't sit on the folded bathroom! It can be used to set things on, though, as we do that all the time. We don't open ours during the day, and only open it at night. DW does not want to go out in the middle of the night, so that was a concession I made when purchasing.
If you always camp where there are facilities, or are okay with using the woods/porta-john at night (you may not get up in the middle of the night now, but wait a few years.
), then you could get by without the bathroom. BUT,
I like it for the shower, also. After a day of hiking, or whatever, I feel better after a shower than I do after a sponge-bath.
The toilet is only half of the facility. The shower should not be discounted, as it is part of the equation.