Any person or group of peoples (in any lower age group than the speaker) who have a maturity level that is equal to, or less than an average turnip.
"Those damned Wiener-Kids! Always fighting about stupid shit!"
"The Wiener-Kids have all decided it's cool to wear their pants backwards..."
"I HATE WIENER-KIDS DAMMIT!"
"Arguing for arguments sake is such a Wiener-Kid thing to do."