It would be fair to say if the event emitter is destroyed then they are unreachable and are released. If you attach to a global event handler or something that will survive a while, they aren't removed because nothing calls removeListener. It would be true of a non-anonymous listener true I guess.
I'm guessing people aren't working out how to remember the anonymous function to then call removeListener. It's one of those, the sugar is so sweet someone didn't notice the sudden weight gain ;)
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