I have always wondered what these are for in the rear luggage compartment, any ideas? They are on the inside of the right rear cubby hole,

I believe those are used to fixate a box, or a smaller item to the floor, as in put the item and put those holders around it, they should attach to your floor via a "velcro" style thing!

No, these are glued to the inside of the lid. My previous car had those Velcro type holders, but this car doesn’t.  It’s just ideal curiosity that prompts me to ask.

I think they're there to hold your velcro holders, which appear to be missing.