If I enter your restaurant, car dealership, etc. then you can pitch & try to up-sell your goods and services to me.
If I drive down a motorway or use your website, third-parties can't advertise their goods and services at me from spots you've sold them. (But you can tell me it will be faster to exit onto your toll road or that I should buy or upgrade my membership plan on the site.)
If I enter your restaurant, car dealership, etc. then you can pitch & try to up-sell your goods and services to me.
If I drive down a motorway or use your website, third-parties can't advertise their goods and services at me from spots you've sold them. (But you can tell me it will be faster to exit onto your toll road or that I should buy or upgrade my membership plan on the site.)