I imagine that that's CYA; one thing both party organizations have in common: they are saturated with lawyers.
And going against an organization that's "saturated with lawyers"?
Even if I were creating a voter registration web site, I'd likely not use this package, as reusing this PDF fulfillment package for any other use within that web site would potentially put the organization in licensing jeopardy. With this license, it'd be safer to re-implement rather than to re-use.
I'm not touching this license with a barge pole.