It'll work all by itself, sucking-up some frequencies, to some degree. But, what frequencies, to what degree?
Most bass traps of which I read are not just something stuffed with anything(Yes, I see the foam ones, but I am not a "believer".). Foam or fiberglass - even a couple cubic feet of same, just aren't enough to do much dampening of bass... The experts seem to say that one must, at least, cover alot more "territory" than the stools would(Maybe if you stack them all the way to the ceiling in each corner??? -- DON'T LAUGH! It's been done! Maybe not with stools?). Still and all, this sort of thing may help, to some degree..? NO!!! WILL HELP!!! Though any improvement may be too slight to notice??? Frankly, I'm not sure how well it would work if you covered every square inch of every wall in the room? Still not with low bass, and you'd have alot smaller room..!(IKea would be glad to have you try, though!) I think it would be better to cut the stools in half, diagonally, so they wouldn't stick-out into the room so much? One, for sure, good thing is that you won't be able to(When playing low frequency tones in the room) actually be ABLE to stick your head in the corner occupied by the stool, to hear if "bass build-up" is still there! Hear no evil, hear no evil, I always say......
Yes, I'm being silly, but, no, I don't think it would "work". It would cost you what, $150 bucks to try, including 4 stools, a trip to Ikea, a trip to Lowes? A "real", store-bought, basstrap is several hundred bucks and you'd need many of them, too, to make much difference. Try it. At least when someone has to be sent to their corner, they'll have a place to sit. Also, while at Lowe's, pick up some nice Poplar and build some bookshelves for your books, it'll help, some... Maybe Ikea(Though I doubt it?) has a very heavy sofa, you could put in your room, along the back wall? Maybe the Goodwill? Much mass, Much density(Too much needed to stuff enough in our rooms!), is needed. Some way of "fooling" the bass(Like the bass trap builders try to do), is likely best. There are plans on the web for such, your $150 may buy enough materials to get a start.
Try it, let us know......
TG