Two reasons I've heard, but haven't tested out personally yet:
1) The pop up results in higher conversions (people actually filling out the email address field and hitting "subscribe")
2) The action of "closing" the modal popup confirms that the viewer of the page is probably a real human and that they genuinely made some kind of movement on the page (scrolling slightly, moving the mouse off the window, etc). This is supposedly taken into account by google, etc when judging page rank for pages.
Thanks for the response.
In regards to number 1 I would be very surprised for that to be true simply because these pages are asking people to sign up often before a user has had time to read the first couple of sentences in the opening paragraph. I guess this is the part that drives me nuts is that they don't give you time to read the content before asking so how would someone even make an informed decision before giving out their email address?
Interesting about number 2.
Is there still not an extension to block this HTML element?
1) The pop up results in higher conversions (people actually filling out the email address field and hitting "subscribe")
2) The action of "closing" the modal popup confirms that the viewer of the page is probably a real human and that they genuinely made some kind of movement on the page (scrolling slightly, moving the mouse off the window, etc). This is supposedly taken into account by google, etc when judging page rank for pages.