So far as I can tell GT relies on people submitting better translations than the ones it has come up with, so that GT can “learn”. I wonder if it’s just so bad that people who can spot the errors are just too overwhelmed by the sheer scale of GT’s uselessness to bother sending in corrections.
Plus there’s plenty of room for japes and giggles. If enough people put in a duff and funny translation, GT will start believing it...