You also have some legal rights as a shareholder. I don't know about the US, but for example in my country there is a LEGAL requirement for companies to maximize shareholder value. Few people seem to know when they blame capitalist greed, when really it is a government law. So you can sue the company if you think they mismanage their assets.

Of course there are ways for companies to rip off shareholders. I think there is an old Philip Greenspun article about it, iirc he mentions buying expensive furniture and artwork for the offices.

I suppose it is part of the due dilligence before investing in a company, to check how they spend their money.