Yes of course, but if the spacing is too much then stuff like this starts to happen.

agreed

If the knockoff is $200 and the same-spec legitimate Pi with warranty is $200, the knockoff won’t be around for long.

Supply and demand aren't a black and white thing, it's a sliding scalre.

More likely the knockoff will be $180 and comes with a knockoff warranty- we make it for $40 incl. parts and labor and sell it for $180, so if it breaks we'll just send you a new one and we're still ahead financially.

What if the knockoff isn't $180 but is $80? Under that condition who would buy the $200 one? If the thing sucks you could literally buy a spare and still be ahead.