Just what I was thinking, only the grout line is outside with tile so you do not see the unfinished edge.
With natural stone I like to hide it and keep it inside.
I try to keep the tile over lapped so water always runs over the edge, grout lines in a box scare me a bit so the less the better (btw...thats a bullnose, its finished). I found a nice blade for the wet saw that finishes the edges the same as a bullnose for only $140 ! Thats a nice look also when dealing with stone