I feel like you get the explanation reversed - everyone gets it, but it's just not that funny. Jokes that aren't funny are off-putting, not attractive.
I should have added *sarcasm regarding the funny part.
I have to disagree though, most users have no clue what that means other than it costs them nothing. And many developers simply ignore and violate the terms because they don't understand the restrictions.
it's not even supposed to be a funny joke. It's just an idea, "think free as in speech, not as in bear" is a plain thing to say just explaining which definition of the word is meant. It's not a joke or clever.
