I'm afraid I can go one better. I sometimes change my stoma bag in the shower (the water helps wash the site, etc).
This is ok...... Unless I've been eating anything recently and it squirts crap over myself and the shower pan, meaning I need to partake in extra cleaning of myself and the shower.......
So, sh*tting in the shower, can anyone raise me on that??
Frankly, it's irresponsible not to.
What, walking down the hall or not peeing in the shower?
I once saw a small girl use one of the display toilets in B&Q.
There was a video of someone's kid doing that on You've Been Framed about 20 years ago when they used to vote for the best video. It won.
I think you'll find there's already websites available to cater for your desires.
Although, a quick word of warning, not all are work safe!
I sit in my cycling kit on arrival at work and go through my emails whilst waiting until I've stopped sweating before going for a shower. Quite often my bladder tells me I can't wait any longer to go and shower.
Really, I sit in my cycle gear and take a sh*t without any issues!!
Some of my old housemates favoured empty beer cans...
Ok, until you accidentally cut yourself......... I imagine.