Samsung smart TVs are the same. I'm normally happy to view adverts if I am benefiting from whatever they fund - TV advert breaks paying for the content that I'm watching, in-app ads because I got the app for free, etc. With the adverts on the Samsung SmartHub all I can see is the software that I have already paid for.

Of course, the demo mode doesn't have advertising, so there is no way to know about it beforehand.

Potentially relevant link: http://www.samsungadhub.com