How does peeing into a bottle save gas?
It doesn't.
I'd venture to guess that I've got one of the longer commutes here (40+ miles each way). I have in fact slowed down, and you know how much it adds to my commute?
Five. Whole. Minutes.
FIVE.
If you can't hold it for five friggin minutes, it's not gas prices to blame. Go see a urologist. Or better yet, as we were ALL told when we were kids, "WHY DIDN'T YOU GO WHEN WE WERE AT HOME!!!!"