I am a fairly new quilter, and I know this might sound dumb, but I can't figure out why people work so hard to get their thread to match their fabric when the stitches are all on the seams on the back and no one can see them. Can anyone explain this to me ?

I don't usually match thread to fabric when piecing. I generally use and off white or light gray for all piecing.

I don't. I piece with a neutral thread. I only match when I applique or quilt.

Because sometimes a little bit of the thread can show, and some people care for it not to be noticeable. Personally I don't care much. It it obvious that thread was used to sew it together, and if it can be seen a bit, no big deal to me.

I use natural (neutral) for all my projects.

I'm not a quilter who uses thread that matches. For most piecing I use an off white, cream or grey on lighter fabrics and black or dark grey on darker fabrics. I only use the colors sometimes in the quilting.

i'm guess that's just a hold over from sewing clothing. with that you do match in case a seam is stressed and the thread shows.
with quilting, we just don't get stress! and the seams really don't either.

For piecing I just use a neutral thread...dark or light depending on the fabric. Maybe they are talking about matching the thread when they are quilting.

I too, am a fairly new quilter, I use a neutral color for it all. I am still in the trial and error mode but if it's imperfect in my eyes, it's probably an awesome creation in the eyes of the receiver.

I don't fret about it. I use what ever color happens to be on the machine. If the thread runs out I grab whatever thread happens to be closest to me.