You can always slightly damage the threads of the fastener thus creating a locking feature and prevents the nuts from walking out. There are a few high temp Loctites available as well which should do the trick, but aside from that... I agree with you
My 26er came with the very cheap, stamped metal, pretend nuts. There was no way that I was going to trust them when I can a couple of old coffee cans filled an assortment of old nuts and bolts. Maybe Weber has upped their game since I got mine. But I would've been
embarrassed to send those cheap a$$, hollow nuts out, especially when someone had just dropped three bills on the cooker.
But, I haven't given it second though since then and enjoy the hell out of cooking on my 26er, at least 3-4 nights a week ! ! !
BD