Weebos are ones who only know pop culture. They have no idea what Japan is really like and see it as a land of kawaii, pocky and anime.Their image of Japan, and how they act (they think this is how Japanese act) is based on stereotype.
We had one in my Japanese lecture. She came dressed as Sailor moon:O Needless to say, she did not last long when she realised it was not going to be watching anime and doing cosplay.
Then there was the anime and manga club at my uni. None of them were Japanese language and culture students....the club was like a group of socially maladjusted who knows what. Fine if children or teenagers act like that because they don't know any better, but adults...
They really do act like this.