You can think about arbitrarily risk-neutral enterprises that are profitable. For example, what risk is a residential REIT taking, especially one whose properties are all insured? By contrast, you can look at a business like a casino (or a catastrophe reinsurer), where it is legitimately the case that operating income is predominantly the result of risk-taking. But when you put the two side by side, there is not a huge difference in ROIC (Return on Invested Capital), which you might've expected if profits were fundamentally a risk premium.
And while lots of businesses do hedge their inputs to some degree, it is not the case that everyone does it to the maximal possible extent.
... no? Just because you've eliminated price risk doesn't mean you've eliminated holistic market risk. For example, suppose you're an airline: if fuel prices go up, and your competitors are not hedged, it's no big deal if you're not hedged, because everyone just increases ticket prices. But suppose you ARE hedged, and your competitors aren't, and fuel prices go down, and your competition cuts ticket prices, and... uh, you're screwed, because 1) you have a bunch of fuel locked in at the higher price, and 2) nobody wants to buy your tickets with the old fuel surcharges. So you're forced to take a loss, and the hedge hasn't actually reduced business risk in this scenario. It tends to depend on the game-theoretic context whether hedging commodity inputs actually reduces systematic risk.
Seriously, hedging price risk in commodities is nearly costless, decisions not to hedge almost never have to do with the actual cost of the hedge. In the real world where things are much more complicated than a toy example, many airlines do some hedging, with the aim of reducing sensitivity of profits to short-run volatility in oil, rather than trying to truly eliminate exposure to fuel prices. But that does come as a "free lunch".
To the extent that it hedges them rationally, they have exactly the same expectation profit. But the bread factory that hedges its future wheat purchases has a lower real profit than the one that does not, assuming the price of wheat doesn't go up, because buying those futures contracts costs money. That's what it means to turn risk into money: if you are willing to bear the costs of things turning out poorly, you can avoid the costs of avoiding the chance of things going poorly, and increase your profit by the same amount.
If you actually believe that a residential REIT is zero-risk and a casino is high-risk but they have the same ROIC, you should buy REITs and short casinos and you can make a big profit. That illustrates why there's probably a flaw in your understanding (though not necessarily! you might be able to make a big profit!). The market should have the same logic, and if this is actually true, REITs will be bid up and casinos bid down until the ROIC on casinos is higher than on REITs, appropriately compensating investors.
FWIW, REITs face a lot of significant risks, eg. a regional downturn could lead to all the workers becoming unemployed and vacating or not paying rent, or a rise in interest rates could increase financing costs, or rent control might be enacted and prevent the property management from raising rents as much as financial models predict. And casinos are actually much less risky than assumed: most gambling games have statistical models for how much they pay out, and with millions of games played reality tends to approximate the models very closely (due to the central limit theorem), and they tend to take out insurance on extreme black swan events anyway. I don't know the ROICs on either of these industries in detail, but I suspect that if it's similar, it's because the actual risks to them are similar.
No, the return on an investment security (in this case, a share of publicly traded stock) is different from the return on a dollar actually invested in the underlying business (i.e., ROIC). This has a lot to do with the price action that you outline.
The rest of your comment deals with why these are bad toy examples, which is fine but not really all that interesting in context.
(As an aside, the EMH is obviously false and you don't need to look any further than meme stocks for evidence, but anyway)
For example, suppose you have two businesses, both of them have a future cash flow NPV of $1 billion. However, one of them was started in a garage with $1 million of angel money. The other one is a "fallen unicorn" that got $500 million of VC money before it finally IPOed.
The ROIC of the first company is obviously going to be something like 500x the second, but this is irrelevant to their market caps, which should be the same in textbook-EMH-land, ceteris paribus.
No, they don't. I'm wondering where people get these ideas.