I would think they would at least run a bead of the grout (guessing they used silicone from the picture) along the bottom just to clean it up...that is what we plan to do with ours. My wife works in tile and stone, I will ask her...or you can also call the company that sold you the waterline tile, they will have a tech support line and can tell you if this is acceptable or not.
I would certainly ask them to grout the bottom.