Shit n' Ditch is the act of using the restroom at a restaurant, convenience store, drug store etc, and leaving right after you 'do your duty'. It's just meant as a pit stop to relieve yourself, and it often causes awkward stares with the employees working there, who know you're not going to buy anything. Sometimes you can't use a restroom because the facility might have it reserved for customers only. This would be considered an unsuccessful Shit n' Ditch, and you would have to find another place, quickly.