Yeah, I'm sure it could be done. I do it all the time with other speakers, but these are big, and frankly fragile due to the glue thing. I think the biggest speakers I've shipped were Infinity Quantums. They survived, but were better built.
I've received several boxes of firewood in the past, they started as speakers...anyway, a skid from Minneapolis to either coast is only $20 more than UPS. Cheap insurance. Easier for me to pack and ship. Harder for magnets to shift, horns to break, corners to smash.
I was willing to get fewer bids due to the shipping method I specified, and the winner, of course, was not having it.
Maybe I'm unreasonable, but the guy knew what he was getting into, then asked for me to completely change course because he was unprepared - both fiscally and mentally.