Overall, vegetarians have better digestive/skin health than meat eaters, but that's a generalization. You're comparing 1% of the population against the 99%, of which 90% are extremely unhealthy. If you compared the healthiest vegetarians to the healthiest meat eaters, there probably wouldn't be too much of a difference. Most americans eat too much protein (and waaaay too much food overall), therefore their digestive systems are way out of whack because their intestines are too full. But you can't say that the reason is due to eating meat. You also can't discount the insane levels of sugar that most people eat too, which slows digestion, causes cancer and speeds up the aging process.
Talk to any vegetarian and they MUST supplement with essential amino acids that can't get in their diet and are only available in healthy red meats and chicken. A vegetarian simply cannot be healthy without animal fats/products. (Only exception: if a vegetarian is able to eat an abundance of fresh, quality fish, this can substitute for meat/chicken, but it's near impossible to find healty, nonfarmed fish nowadays). The japanese culture used to be the healthiest in the world because they ate quality sushi mainly. But their foods habits have changed due to communistic laws which reduce fishing and increase prices.