Apple need the 30% to keep the services revenue up to keep the stock price up. I have no doubt many people at Apple know this is wrong, including the people at the very top, but stock must not go down.
I always had a mild smile for the tales of the "secure refined Apple store" but seeing the reality has been a bigger shock than I expected. It's a scam haven.
Insurance companies have lots of competition, also low profit margins.
Making a top of the line smartphone does not have a lot of competition, hence higher profit margins.
Medicine is patented and hence does not have a lot of competition, also higher profit margins.
We don’t know what that is, since there currently is no market.
Sure, technically it's still a market, but I wouldn't consider it a remotely efficient one to do price discovery.