I'm not much of a gourmet myself but here's my question: If you buy "wild salmon" and believe it's wild salmon and enjoy it, isn't it just as well that you were able to save a few bucks because you were misled? It's mind over matter. I'm not defending the lying liars who are pushing diluted maple syrup but it's actually healthier if it's thinned out a bit with water. And if you can't tell the difference, who cares? Just be grateful that there's no lead in it.
On some products it matters more. Olive oil is popular in part because of strong evidence of its health benefits and depriving people of that with mislabeled benefits poses a serious problem. In any case, we should not start falling prey to this sort of scam. Today, it may just be water added to your maple syrup, but who knows what's next?