Just to lock this one down, the shoe thrown ambiguity is fine because the joke is funny either way. Similarly the Impy and Chimpy one is still funny.
However, Grandpa Simpson just entering the Burlesque house then leaving again because he assumes he won’t get past the door guy isn’t really very amusing, it’s straying into the surrealist. Whereas the true reading - and we know it’s the true reading because we all post it to express this sort of point - is far funnier with him clocking Bart and immediately, and smoothly pretending he absolutely came to the wrong place and leaving again without a word. This is an early Simpsons so we know it will be the funniest it can be.