JPGs created, what's going on?

Question

I usually shoot JPG although I have a few RAW photos. My camera when it saves RAW saves only RAW, not RAW and JPG. I was looking at a directory today and noticed that the RAW files all have associated JPG files with a recent creation date (not the same as the raw).
Looking more closely I see that these apparently rather low quality JPG files (from their file size) were created on the day we were having the discussion of the missing metadata in JPGs. I had turned on "Automatically write changes to XMP" in Preferences, which precipitated Lightroom writing out every single file in my catalog.
Apparently it also, in its wisdom, created JPG files of each of the RAW files. Does anyone know what this is? I won't set that option again but I am curious about this "feature."
Of course, they don't show up in Lightroom itself because they have the same name as the RAW file.

Answer 1

I'm sorry for the confusion. My camera is making these files. However, there is a Lightroom issue related to it.
I thought I read that the camera didn't create both a JPG and a RAW but it does. It creates a low ("standard") quality JPG. Here's the problem with Lightroom. It imports both files but registers only one (as we know, since they have the same name).
Even worse, if you delete the cataloged one (RAW), it does NOT delete the low quality JPG. This is not good because I don't know how to keep my directories clean if Lightroom imports but will not delete files.
It is also curious that the date on the file was the date and time of when I set Preferences to Automatically Write Changes to XMP. That means it doesn't only write to cataloged files? I checked the metadata in one of these files and it does contain information that I entered for the corresponding RAW file in Lightroom.
Lesson to be learned here. Some of us are getting our directories cluttered with stuff that is not cataloged in Lightroom. How do we keep them clean?