Yes, but if you don't know that they make no sense and if the majority of people listenting don't know that they make no sense, does it matter terribly much if a few people sing it wrong? Its just a mangled instance of the song, it doesn't usually do any damage to the actual song.
I used to work with a lady who sang all the time - little snatchlets of mangled songs - cobbled together as she went along. It was lovely, and I always so admire the fact that she had the urge to sing while she worked & just went ahead and ad libbed. She was actually quite shy other than that. Such a nice lady.

Kris