Why did ponyboy say an you can shut your trap to johnny cade cause we all know aint no one wants you at home either and you can't blame them?

Ponyboy says this to Johnny out of frustration and as a way to express the harsh reality of their lives. Both characters feel isolated and unloved, and Ponyboy projects his feelings onto Johnny, highlighting the bleakness of their home situations. It's a moment of vulnerability where Ponyboy acknowledges their shared pain, even if it comes across as cruel. Ultimately, it's a reflection of their struggles and the emotional turmoil they face as members of the Greaser gang.