No worries. There are checks and balances.
Minority stockholders have a number of options (pun not intended) in terms of litigation. I start Go-around Corp. and make 737 landing gear. I sell you a minority stake in Go-around. And after you're onboard, I use the capital to make war on Canada geese. I cover the American east with goose traps, auto-turrets, I'm wasting all the company's money on a wild goose chase.
You get to sue. You get to argue the case that my priorities are twisted, and that I'm not acting in the best interests of the company -- which bottom-lines to the bottom line. The judge goes "Yeah, you're not acting the way a company is supposed to, which is the pure unrelenting pursuit of profit (moderated only by an entirely reasonable mission statement, which is known for a long time and generally consented to by shareholders), and modulo modest deflections toward goals other than profit. But these are modest.
So for instance Target can give 5% of its profits to the community when it doesn't have to - but if it did 90%, the minority stakeholders could sue. 5% is modest, 90% isn't.
There is now a thing called a LLLC, which is a for-profit business with a mission, like a nonprofit. They get to prioritize mission (somewhat) over profit, but they have to say so up-front - so as an investor, your eyes are wide open. I could start the Goose-A-Way Landing Gear Company, and our Bylaws state we spend 90% of our profits eradicating Canada geese. But Boeing doesn't care who builds its landing gear, so the mission would be like an albatross around our neck - we would fall out of formation with competitors, since business profits weren't being reinvested or paid to investors. So LLLCs tend to exist for luxury consumer products where people are pleased to pay a premium for socially conscious products.
Here's an example of a lawsuit by minority owners at OP's example company Facebook: https://www.theregister.co.uk/2019/05/31/shareholders_win_demand_for_facebook_documents_on_cambridge_analytica/
A court in Delaware has backed investors who want to see internal emails and other documents relating to how Facebook handed data on 50 million users to Cambridge Analytica.
The ruling (PDF) said that shareholders provided enough evidence to support a claim that failures by senior management and board members at the social network may have allowed the illegal data slurp to happen.
