With the keyword here being big projects, yes absolutely. A lot of the time if I'm working on a bigger project, I'll prototype individual parts as their own games to figure out mechanics, tweak them, and get myself to fully understand the system before implementing it into the main project I'm working on. Do I ever release these? Rarely, if anything maybe as part of a game jam.
And like others said, it's a great way to get yourself over roadblocks, try similar things from different angles, or just get your mind back into thinking creatively when you feel like you hit a wall on the main project.