We have them in the basement along the sill. They seem to be down there in that cold location thru the winter, also. They never show up anywhere else but they are down there just like in the last home where we lived. Nearly 25 years of sharing a house with black widows, I've yet to find them anywhere else and it takes a close look to find them there.
Cardboard lying on the ground you say, Elf? Somehow that makes some sense with living along the sill of the house. "Dry places with low light" ? Yeah, that seems likely, also. Sneakers in the laundryroom, Vfem? Yikes! Glad I don't have to put up with that!
Hobo spiders are far more common here. Or at least, one comes across them commonly. Sometimes, they
come across the person like running over them in the bed during the night!

Dang

! There seems nothing much that can be done about real chance encounters. And, the smaller, immature Hobo is supposed to have more toxic venom than the larger ones! It is good to have some kind of idea about habitat but the Hobo will just turn up anywhere! Maybe that's how he got his name.
They are in Europe and the Pacific Northwest. Oddly enuf, they don't even range down into northern California but are on into western Montana.
Yep. Give me a friendly and harmless Harvestman any old day. I always try to leave him alone in the garden and appreciate him being there.
Steve.