I am at the Paypal website almost every day and it does not stay open. If there is no activity after 5-10 minutes you will be logged out. I think the website you were at may have been fraudulent. Are you sure the PP site where you did not have to log in was the real thing? Scammers have ways of re-directing you when you are trying to get to a legitimate website and you wind up on a fake look-alike site.