In his book, Anger is an Energy, Johnny Rotten says:

“That line, ‘I wanna destroy the passerby,’ I was talking about all those kinds of people, the complacent ones that don’t contribute, that just sit by and moan and don’t actually do anything to better themselves or the situation for others. The non-participating moral majority. I just thought ‘passerby’ was a better phrase, gets to the point quicker. Rather than use twenty-two words, just one nailed it rather well.”