What the fuck happened here?

The cover page of one catalog got stapled into our Lamps Plus catalog.

Complete with our correct name and address on both catalogs.

And the random catalog page was printed off center and cut off on the edge.

somebody's last day at work giving no fucks?

That's a fair guess.

It's like a more benign version of those Bibles that people printed with random inserted, often offensive bullshit.

or, now I'm thinking about it. Sometimes my Smithsonians come with a 2nd cover over the first, usually if they're in a donation drive or advertising something, I wonder if your expected catalog meant to have a 2nd cover but someone forgot to empty the machine from whatever ran through first before it got collated

That's possible! I've gotten the Lamps Plus catalog before and it never had an outer cover though.

it shall remain a mystery!

a really weird, badly cut mystery XD

Indeed. XD