Yes but they understand that in free market, they have to spend money on quality employees to make money. Hence, people still invest in companies where employees are treated better than their competitors.
Unhappy employees is not good for business over long term. That is why you see in news that racist, sexiest, or other bad actors getting fired even when they were top performers.
For a lot of them, no. Also, even if they only want to make money, they will have different opinions about how different company strategies will succeed, and be interested in different time frames.
it isnt typically the only goal, no. Many people own stocks and stakes in companies because they believe in what the company is doing, producing, or working towards.