I was just like you for the first 30 years of my life, and then I realized that all I gotta do is wet two paper towels, put soap on one of them, and use them to clean the seat before I sit down. That small realization completely changed my life for the better, and now I no longer have to wait until I get home to poop.
(That said, 30 years of holding in your shit has consequences. It takes me from 20 minutes up to an hour to poop before I can get it all out. Needless to say, this had caused issues for me in the workplace. Yes I've already started adding fiber to my diet. And before you ask: no I don't flush the towels. I toss them in the trash can then head back to the stall to do my business.)