My two yen...
shoshana,
A lot who already posted to your reply (Jazzysmom, EnergyGal, Kayleesgrandma, mamerth) have pretty much stated what I would only confirm.
I, myself have been on here for over three years, and have seen many a disagreement, and have even been the object of a few.
If there is anyone in particular you feel disgust in their post, there is a function available to "block" their posts. I know it's sad to even resort to using such a function, but if you are really feel offended by the person, you can block their posts.
I would, however, just try and get used to the diversity of members to this group before making such decisions as to leave the site, or block the members you find offensive.
My first time on here, I felt quite nervous about how I word things, and even now, I re-read my posts at least once for it contents, but although I wish everyone could, not everyone would.