People value the market by multiplying the stock spot price by all issued shares--and that's obviously wrong.
Well, it's actually obviously right. Everyone who owns that stock has the option of converting one unit into that amount of money. Why wouldn't they? Because they value that stock at >= the stock price. Otherwise they'd sell for that amount. I mean, sure, some investors are probably asleep at the wheel (and that can be fine as an individual) and have let the value drift above what they would value the stock at, but generally there's going to be enough active traders that the stock price matches what people think the stock is worth. If it was too low, more people would buy. And if it was too high, more people would sell. That's how markets work.
And why do people value things as they do? Clearly it's not coincidence that, say, Rogers Sugar stocks are valued what they are. Investors - in aggregate - figure that, for the amount of risk and potential Rogers Sugar represents, they expect about a 7% return on investment. So their stock ends up being priced such that that's the return you get - the price effectively seeks that value. Again, if people were willing to get less than 7% return from this company, they'd buy more and push the stock price up such that the return was lower. If investors, in aggregate, demanded more return, they'd sell the stock, the price would go down, and the return on investment would go up.
You can only get out exactly what was put in.
Companies grow and become more valuable because they earn more profit. As a shareholder you own a percentage of a company. As that company grows, the value of your investment increases.
So of course you can get out more than you put in.