I use them on everything.

On some applications I use light springs that require being substantially compressed to store some energy and hold the car at ride height. Takes some effort. Front springs are worse because of the spring rates, especially on A-arms. I don't like busting my knuckles or damaging parts. On an aluminum body shock with coarse threads, it helps reduce the likelihood of damaging or tearing up the threads or the adjuster.

And I use spring heights to adjust corner weights, ride heights, level, etc., so it's not usually just a set and forget deal.