Mondregreens are great.
Even Bob Dylan got confused when he offered the Beatles some grass and discovered they had never smoked before. He thought "I can't hide" from "I want to hold your hand" was "I get high".
"Don't bring me down, Bruce" from ELO fooled me. It is actually "Don't bring me down, groose".
Even Iron Butterfly intentionally did it after Doug Ingle got drunk one night singing their new song "In The Garden of Eden", so it became "Ina-Gadda-Da-Vida" instead.
And who can forget "Excuse me while I kiss this guy" from Purple Haze. It became so prevalent that Hendrix would point at one of the band members when he sang it on stage, and even deliberately changed the words during performances at times.
The lyrics to "Louie Louie" were actually investigated by the FBI after they were reported to be "dirty". The FBI eventually gave up.
Steve Miller Band's The Joker is another famous one. The actual lyrics are "'cuz I speak of the pompatus of love". I always thought that one was "prophetess of love".