One useful test of science if the property of falsifiability: what would it take to demonstrate this theory is incorrect?

Without that attempt to prove the theory false, I don't think it should be considered scientific.

So, for instance, expose someone to a lot of advertising and if they don't seek out the thing they are exposed to, then this theory (at least on this basic level) might be false.

Well, you might say, the claim is not that the person will definitely seek out the familiar but is more likely to do so.

Then propose an experiment to test this. Now we have started a scientific discussion.