I love listening to my pipes with full unplugged clarity, although I am sure like everything if you play at a constant db level you will effect your hearing.
So perhaps it isnt a bad idea for players, but for spectators they may want to carry a pair of ear plugs any.

By the way to make a pair of earplugs I keep the foam peanuts from packing boxes and cut them into two.
Works well and you can still tune and play then throw away at the end of the performance.
Or send me $5.00 and I can make a set of twenty.