I have heard of it, but never for mail order.
Cabelas in the next state over would sell to me face to face, but required the address on my driver's license match that on my FFL.
I have bought from some places
that would accept a scanned signed copy, and others
wanted a hand signed copy by mail. My first purchase with my FFL was off Gunbroker, and I included a signed copy with my payment.
Hopefully it is just a guy who is not used to dealing with 03 FFLs and just wants to cover his arse.