Correct you took no action to interface with them besides walking. But if you walk into a room where just a musician is playing(and its advertised that this is whats happening in the room) you have now created a relationship where you've chosen to receive their art. And if they have a poster for their sponsor on the wall behind them you can't complain about it.
Trying to explain this has failed an innumerable number of times here. Whenever this discussion pops up, there are die-hards who are against all advertising versus those who present a rational argument explaining how the content they willingly consume is supported by those ads. Like wrestling in the mud with a pig, you will come out of this unfulfilled while the other side comes out feeling like the winner. They're just a highly vocal minority.
I'm not a personal fan of ads but when it comes to things I find important enough and have the option, I pay to remove them. The difference however is that the die-hards tend to not accept paying or viewing ads as acceptable. If they did, this wouldn't keep coming up.
But nobody told me what was happening in the room before I walked into it. I saw nothing but a URL, or maybe I saw some text obliquely indicating what might be happening in there. I certainly didn't see the text of a contract before I walked in. If I walk in, not knowing anything, how can I have signed a contract?
Similarly, if I have no binding contract, it certainly can't be required of me to observe or respond to everything within the room. There is no origin for the musician's claimed right to oblige me to any commercial action.
