BoC’s still exist (and the previous owner has a new site with a similar occasional gimmick), but those at least give you a laugh.
I got a gift subscription to Loot Crate for a year. I kept under 10 things total from all of the crates. A few of them I brought in to give to coworkers, but most of it went right into my donation box.
All of the stuff in the crates is sold on the site a month or so later in their store. Instead of buying a box of random junk, you can just buy that single item for a fraction of the price. Or buy it off ebay from people who are trying to recover some money on their investment (very common, in my experience).