I agree with Dizzwave that the rule should be this: use hyphens only where they reduce confusion.
In the case of "our more educated patrons", "more" is an adverb that modifies the adjective/participle "educated", which is quite regular; it cannot be taken as an adjective, because "our more" would prevent that; therefore there is no substantial confusion that could or need be solved. The same applies to "less educated" in nearly every context.
In "our college-educated patrons", there are several ways the reader could theoretically be led onto a false scent:
Our college educated patrons of nearby
establishments so as to improve their table
They told our college educated patrons
should be seated at the back of the
hall [= They told our college that
The reason why "college" is more prone to confusion is that it is a noun: nouns are most of the time more fundamental elements in the construction of a sentence, and nouns most of the time do not modify other words.
That is not to say that adjectives/adverbs cannot be confusing. In fact they too require hyphens in some cases, as in the following example:
A fast dying rabbit
Is the rabbit fast but dying, or is it dying fast? If the former, a comma should be added; if the latter, a hyphen. The reason why "fast" can be troublesome is that it doesn't take the regular adverbial suffix -ly that most other adverbs do.
This rule means that compound adjectives normally do not require hyphens for clarity if they are used predicatively, i.e. as subject complement with a copula, such as after "to be":
Most of our patrons are college
One last thing to consider is consistency: it is generally easier for everyone if the same phrase or word is written exactly the same everywhere; this makes it easier to recognise for eye and mind. That could be an argument for using hyphens in compound adjective universally, even where there is no confusion. However, current practice and nearly all style books find this argument too weak and stick to the rule "use hyphens only to reduce confusion".