Alright, NO player can use them. (Just wanted to get that straight so you don't say NO immediately). Now, the point is for the map.
1.If the server hoster has a map he doesn't want destroyed, he could toggle "Indestrucable mode".
2.Of course players could build and destroy their own/enemies blocks
3.but the original base blocks for the map can't be destroyed.
Good Idea? You decide. Just, don't run off-topic and keep level-headed in an arguement.