tl;dr: these are a joke on the NIST curves and the "verifiably random" way in which they were defined. While being safe curves, they've been tweaked to include the hex string "BADA55" in the "verifiably random" B constant derived using B=SHA3(seed). This demonstrates how other curve parameters could've been tweaked (by, say, the NSA) even in a "verifiably random" standard like the NIST curves.

At the same time these could conceivably serve as drop-in replacements for the NIST curves, but then people would have to recognize that djb is a BADA55.