Always thought the line was read with a bit of nostalgia, like ‘heh, oh yeah, there was this one time’
Imagining how Homer found himself in a situation where someone says goodbye to a shoe is where the #comedygold lies. Lets the audience make the connection, which is funnier than spelling it out
The fact the line was improvised is neither here nor there because the author is dead and therefore not the source of the meaning of the text