Cats do this when i leave?

I recently discovered that upon my leaving the house, my cats leap up onto the curtain on my front door. They jump up, grab ahold, and hang onto the curtain so they can try to see me out the window.

I noticed little holes in the curtain but I didn't know what it was from, turns out it's from their claws. I found out because I went out onto the porch to talk to someone outside and up they went onto the curtain, hanging on with all their might, peeking out the window. I did a few experiments to see if they do it every time I leave and they do!!

It's kind of weird because I didn't think the cats gave 2 shits if I left. They aren't very affectionate most of the time either. Either they miss me or they are making sure I'm gone so they can do secret cat business, I dunno.

IIN? Do your cats do this?

As you can (sort of) see, the curtain is covered in little claw holes!