The usual method is to leave a single grout line space at the bottom. That joint should be finished with caulk, not grout. It shouldn't cause any functional issues though, and if he does a nice job of finishing the vertical grout lines that touch the counter top, it might just look awesome.

Thanks for that dseng, but I'm concerned about the movement of the tile itself (expanding/contracting) and worried that the tile will end up popping off the wall? He has also installed with 1/16" grout joints (at my request) which now I read might be too small and cause the same 'popping' issue down the road. What do you think? Grrrr!! Biting my nails now :-(

The movement of the glass will have a lot to do with the temp variation of the wall it's mounted to. Especially because you have 16th inch grout, (did someone recommend that, it's very unusual, and not typically recommended). So If you live in cold climate and the kitchen is on an exterior wall, depending on the insulation, you may have a problem.

You may want to consider having the bottom row of tile removed, cut and reinstalled

By the way, tile should be installed from the center out, always.

If this is inside the house, you really shouldn't be getting enough expansion and contraction to cause things to move. If you are, you'll have cracks in your grout and tiles breaking free from the thinset (he did use thinset and not mastic, right?). There's always felixnot's suggestion of having him pull and cut the bottom row - the cut edges would be covered by a nice, neat, professionally done caulk job.

jmcn608, I just had a horrible tile installer do the same thing after we spent a fortune remodeling our kitchen. I'm curious, did you leave it or have it redone. And has the grout or tile cracked since. We haven't grouted yet and I'm debating if I should take out the bottome row.