Flooring Tile - "Professional" tile install - didn't use spacers

We just had a bathroom floor professionally tiled with 12" tiles. My wife just informed me that the installer didn't user spacers and she isn't as happy as expected because of variations of tile spacing. I haven't seen it yet so I don't know how much variation there is. Do professional installers typically use spacers or not?

Also, she isn't happy with the cut on one of the tiles in the corner next to the door. (Tile was done on a diagonal)

We can be a bit of perfectionists, so am I out-of-line to complain to the store we hired?

Hard to say without seeing it, but if it's bad, complain.:)

I never use spacers on floors, they can throw you off if the tile isn't all exactly the same size, I grid my floors with chaulk lines or use my laser.:)

Thanks. It turns out that he did a pretty good job except for some of the caulking at the edges and one tile that is quite uneven with the rest of the floor.

I wouldn't have posted if I saw it myself 1st, but wanted some opinions since they wanted me to pay that evening.