In email just as in snailmail
Several times I've wondered why the Repooflican party sends out donation requests in envelopes that look way too much like official IRS notices. It's on the edge of the law, and it has to be counterproductive. Back when I was still a fairly loyal Repoof, willing to give if approached properly, these IRS-notice letters turned me off.
They use a similar puzzling technique with email.
The first email in this list is from the Wash State Repoofs, and it's typical. Blank return address. Subject looks like Nigerian spam. No sensible person would ... Oh. That's it! Nigerian spammers make their appeals blazingly obvious to filter out sensible people. Cultivating a mark takes a fair amount of work, and there's no point in starting the process with a prospect who might see what's happening. Same with Repoof spammers.