Highly likely because MailChimp is a BUSINESS site, not some consumer site. Normal people love to just click a button and see their facebook image and name saying, "Welcome back, John Doe!" - without any pesky emails or other junk.

Aren't most of the people logging into Mailchimp online marketers? Maybe "technical" is the wrong word, but their customers are all in the tech business somehow or another. I think that qualifies.