IMDb.com arbitrarily created a new account for me

Hi,

Weird thing just happened.  I Googled a movie.  I clicked on an IMDb result for that movie.  I viewed the page, scrolled around a little bit, then closed the tab.  Pretty normal behavior, I think.

I did not click on anything.  I didn't try to post a comment or a rating or anything like that. Definitely didn't try to sign up/in.  All I did was view the page.

A few minutes later, I received an email saying "Welcome to IMDb!"

I went back to the site, and lo and behold I now have a new account.

I use different email aliases for different vendors/sites, mainly to cut down on and track spam.  The new IMDb account was created under my Amazon-specific email.  I had indeed been logged into Amazon on that same browser.

I know IMDb is owned by Amazon, but I've visited the site countless times in the past on that browser.  I'm always logged into Amazon on that browser.  Yet this only occurred now. 

Is it just me, or is this a new thing they're doing for everyone? 

The real issue is that I've already had an IMDb account for a while under a different email, so this is kinda redundant.

Moreover, when I tried to log out of the new account and back into my main on that browser, imdb.com threw a 500 error.  I don't think it likes the cookie situation here.  Hence I'm posting this from the browser on which I'd previously logged into IMDb on my old account.