In most corporations, the only thing that shareholders really do is vote in relation to who the directors are. The directors and officers are generally the ones who actually do things.
The directors are often also in charge of share sales and transfers. In corporations not in the stock market, you often can't sell, redeem, gift, or otherwise get rid of you shares whenever you feel like it.
Officers are also appointed by directors, not by shareholders, so that could be another step removed from having agency over what's happening.