On Sunday, October 1, 2017 at 9:38:56 AM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
It's to keep "bots" from grabbing email addresses and then spamming them, bots usually ignore the "encryption", but humans can figure it out.
Headers from posts are also not usually visible to a bot.

Plenty of tech peeps here that can expand on it if you ask.

It's largely a silly waste of time, bots certainly scrape the headers straight off USENET without going though Google Groups. Bots can also reassemble the "encrypted" silliness. Of course what they scrap from headers might be fake or burner addresses... up to how paranoid and hard to contact you want to be.