nope, Spanx are full-on spandex pants and must be pulled up and down (as with any undergarment which encloses one's nether bits) when using the ladies room.
My mum bought me loads of spandex lycra and splanky undergarments even though I was only 20 or 30 or 40 and didn't need them. I now reckon she was sending me all her cast-offs, stuff which was never going to fit her and which I'd just scream at.
I'm still okay and don't need an all-in-one, but I'm going to end up looking like my Mum...
Re: women peeing standing up. I can do it. It takes practise. You need to do it the first time indoors, in a safe place, a totally tiled bathroom. This I did in a male friend's toilet due to the fact that he'd pee'd allover my loo seat for years on end. After I'd figured out he was doing it on purpose, I used to run in there before him to lift the seat. So when I saw his brand-new designer-built totally tiled bathroom, I pee'd standing up. No problem.
After you've tried it a few times, you can do it outdoors (if you're in the middle of nowhere or behind a bush) without blinking. If you cock a leg sideways (this only if someone has followed you) it really makes people laugh.
Obviously you'd need to have to go really really badly in an emergency. Ordinarily we women are able to hold it and wait forever (usually till we find a pristine public loo or get home)
Or you can squat. I've not sat on a public loo seat since I was 16. I've learned to squat and aim. I kick the seat up first, then sometimes put it back down.
I'm so flipped out by nylon and spandex that I can't even bear bras with padding in them. Yuck. What are they about? Beyond me. It's difficult to find bras without padding and push up these days.
xL
Pink plastic funnels are for girly girls who wear pink nylon underwear and lug about large pink plastic handbags, then chuck their knickers in their handbags when they've finished?
All you need do is whack up your skirt or hoist down your jeans. Have kleenex or a hanky or a sleeve cuff handy if you don't want to drip dry.