Once a plant like cabbage for instance bolts, it won't unbolt, but not all is lost. If you desire your own cabbage seed, let it go. If you have livestock or chickens, they'll likely eat it. And of course, like you mentioned, composting is always a good way to make something useful out of something undesirable.
"Study books and observe nature; if they do not agree, throw away the books." ~ William A. Albrecht