RK, what is so detrimental about a water dish?

I personally don't use them much with adults because they don't use them much. But juveniles tend to enjoy them, and seem to need them the most. One can certainly get along without using a water dish with a HL...but why would it be a "detriment" in any way to use one?
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"A man that should call everything by it's right name, would hardly pass the streets without being knocked down as a common enemy." The Complete Works of George Savile, First Marquess of Halifax 1912,246