Whether you like it or not is your choice but these are risky investments. A company buying BTC with the investors money and using the profit to give back what it has owned. Its similar to "give me your money, I will double it back".
I would never suggest someone to invest in such companies or buy their shares. Buying bitcoin is much safer instead, but people have a notion that since the BTC they are not directly buying, they are devoid of it the risks it pose, which is a fundamental mistake.
Any company will go down, the creators of the scheme may have left by then but your money will get stuck at some point.
It's how people can be scammed easily because of "too good to be true" offers, they want to get rich easily, quickly without efforts of learning, managing risk, managing their money, so it's perfect chance for scammers to do their scam jobs.
Ponzi starts with money, it's definitely right because without money attraction such as "double your money for profit", there will be no people fall to Ponzi scams and become victims.
People have to know the most basic thing, if making profit is too easy like this, where is the money comes from, and if it is actually easy, all people globally would have been rich already. They only need to open their eyes, see the fact that there are the rich and the poor, so there is no easy get rich quick chances for everyone.