They peck at it a little bit, but not much until I take a big solidified chunk of it (moist air makes it clump) out of their salt pan, and put it on top of their grit container (which they pay close attention to).
Then over a period of a couple of days it disappears. About 50 birds eat about a 3 inch diameter flattened pancake of it in about a day or two.
My other two pens with 11 birds and 19 birds go through it more slowly. Actually it does get pecked at every day, but in minute quantities.
But they DO enjoy it. I worry they will go for blood (salty) if they don't have it. I also put out some of those red brick mineral blocks. But I haven't noticed them going for those at all. I don't think I will rebuy them.
They really don't go overboard. I have tried dumping out a LOT of salt in their grit pan, and they just move it onto the ground. They self-regulate.