Landlords cannot just evict renters based on the landlord's own terms of service, not even a renter's non-paying children or girlfriend with whom the landlord didn't contract, and not even the renter himself although the stopped paying: The landlord needs to follow the rules of society, go through a bailiff's court or follow similar strict procedures defined in society to ensure that mandatory law is followed.
Not everybody can set up a medical clinic on their private property, even if they offer their services for free.
TV stations in many European countries can't show hidden ads in programmes and cannot show ads for kids for certain products. Even though the viewers didn't pay. Even though they are free not to watch.
In most places landowners cannot freely decide to do what they want with their land, like building a factory, without taking into consideration zoning laws and without hearing the neighbors or wider community as well.
For millennia, what we today call criminal laws, have applied on private property as well. You can't just hit somebody in the face because they are in your house and the terms on the door clearly says that you can. Think that's ridiculous? Well, it used to be that restaurants in America could chose to serve whites only. It was the choice of the property owner. Until it wasn't. Courts and congress decided that such practices were so despicable that the general interest of non-discrimination outweighed the interest in business owners getting to decide for themselves. Same with businesses hiring men only. Today most of us regard it as obvious that non discrimination laws trump the interest of private owners. A few decades ago, most people thought the owner could choose freely whom to hire.
I hope we will start regulating the new advertising industry comprised of social networks and search engines more tightly.