You're right, by cracky! I used to think that "youse" was a Chicago or Joisey term, but at this very time we are hosting four visitors from upper Minnesota....and damned if they don't say "youse" alla time...you betcha, by golly.
"Youse" is big in SE Pennsylvania (Reading to Philly). I can't count the times I had waitresses ask "Are youse ready to order?"