I am occasionally asked whether I am not afraid that someone will steal ideas from my blog and publish them. I'm not. If the ideas get published by someone else, that saves me the trouble of writing them up myself. Hopefully they will give credit where credit is due and it won't be theft.
Moreover, I invite anybody competent who wants to coauthor a paper with me by starting with the ideas in a post, working out the details and writing up a first draft. (Check with me first before getting to work, though.) In the philosophical profession, coauthored papers count pretty much the same as single-authored, so plagiarizing would involve unnecessary risk for very minor benefit.