All depends on your team and the situation. Scholarship resources, as we all know, often end up going toward lost battles. And valuable players can be found for few resources. But at high levels of D1, if you're typically fighting only for elite level players, it doesn't make a lot of sense to try to hold on to him. The typical walk-on you get at A-level D1 schools can play *a little* if you absolutely need them to, you can think of them like 1-year transfers, no need to give them a scholarship.
But if you're in a situation where you're looking at a bunch of pending EEs and you've already lost some recruiting battles, well it might make some sense. I probably wouldn't even think about it until the very end of the season though, only in the case of a disastrous 1st session of recruiting, sort of the same scenario where I redshirt a senior I left off the depth chart all season. Not a typical occurrence, but might pop up now and then.