If it's not too late set fire to them and claim they were damaged in shipping or something. Maybe even leave the package setting out and hope someone steals it.
Or... actually receive the GPUs, and pull 10 older dual-core rigs out of my warehouse, upgrade them with said GPUs, and sell them all for $250 ea. as "budget fortnite boxes".
Or do the same, but give them out at the local food pantry.
If my perusing through craiglist is any indication, getting to 60FPS at 720p low in Fortnite is right at the cutoff where you package it with an i3 and your leftover 2002 case from a P3 system and toss it up for $1200 as a "Midrange Gaming Computer"
Yeah, basically, this, but maybe give the final "product" away? OTOH, other system builders in the area might not appreciate it. Then again, if they're building "Fortnite gaming PCs", with GTX 650 1GB cards also, I don't think that they can complain.