Opinion on a wider grout.

I had a tumbled bronze travertine Marble (http://www.lightemprador.com) backsplash - 6 x 6 Tiles (http://www.g682.net) - installed last week.

I told the installer that I wanted the grout joints very thin and (http://maplered.com) not obvious - and (http://maplered.com) also offered him to use the unsand (http://maplered.com) ed grout the Stone (http://g603.net) supplier sold me when I bought the Stone (http://g603.net) .

He told me there needed to be some width of grout joint because the Tiles (http://www.g682.net) have irregular edges (which, to me ,seemed no big issue). He came the next day and (http://maplered.com) his installation consisted of using sand (http://maplered.com) ed grout! with grount lines maybe 3/8" -and (http://maplered.com) noticable (although thank god the color is close to the Stone (http://g603.net) ). To me, this guy just did the job the way he wanted to  do it - and (http://maplered.com) although the Stone (http://g603.net) looks good installed, it is not what I wanted installation-wise. Is this a common practice for the contractor to just go by his own guidelines of what he thinks is right??

It really aggravates me when I see Stone (http://g603.net) installations w/o a noticable grout line like I wanted. My wife tells me to forget about it but I can't bewleive he did it that way.

Your opinion on the this. Did I NEED a wider grout because of that type of irregular Stone (http://g603.net) ?? Please advise