Quite the contrary if the flaw is built into the base of the system. If you base the economic system around the accumulation of property, you can’t expect people to do things out of abstract ideals. Your idea of capitalism requires selflessness and altruism which are not rewarded in that system.
In a college lecture, you can gain new information and ask questions. Local government meetings like public consultations about new projects - you can push for a certain outcome.
Political rallies - I reeeally don’t get it. The fact that you even go means that you support the candidate and know their positions. It’s unlikely they will say anything new. It’s usually just a series of soundbites repeating the same ideas that you likely already agree with, otherwise you wouldn’t be there.