I really don't like your definition of 'free'. wikipedia has been relying on donations for quite some time. guardian.co.uk is one of the recent examples asking for donations and working out for them.
>science articles
Ok that has to be a joke, the paywall journals subscriptions are nothing like ads.
Please, don't conflate any pay method with pay wall (which is a pretty good one). If business cannot retain itself w/o breaking the law and has to shove unwanted images/videos/etc. straight in the face, it may as well not exist. The ads have degraded user experience in so bad ways that having a page with little content and 'next' button just to show more ads is pretty much the norm now.