I do keep one in my back meadow and as KentuckyTJ says, the deer visit them most intensively in late winter into spring.
But when hunting, they are illegal here. When I find one in the field, I pull it.
I once had a great elk hunt ruined by one. I'd hoofed and hoofed and located a big bull. I waited 20hrs for the wind to stabilize. He came to my call hot and heavy. I didn't get the shot, but it was pretty exciting. The following day, on my next attempt, he busted me. When I checked out the area he'd been hanging in I found a salt lick. I was pretty mad about that.