Yes, It's ponzi site!
We need to stay away from those site, They scammed thousand of peoples every years.
Like Hashocean, I personally have scammed for 100$ in this site.
I don't advice people to invest in cloud mining sites.
Hashocean or not i wouldnt still invest again on this so called cloud mining site because they are just total scams for me. This scheme would continue to pop out everywhere because there are still people who used to put their money on this schemes as i observe on recent post those newbie accounts trying to promote the site is paying. I already know their style on convincing people they may convince some but not me.

Finally some one that isn't talking nonsense. You hit it exactly on the right spot.
The only reason cloud mining and other scam sites exist, is because of dumb people pumping their hard earned cash into these sites as they seriously believe they can make profits.
Some people even know they are "investing" money into an obvious scam site. They think that they can walk out with profits when they are pumping money into that site at the very early launch stage.
Even though noobs invest without doing actual research, I feel sorry for them if they lose money due to scams, but that's not the case for people knowingly "investing" in scams. It's their own fault.
Yes, they join this kind of site, because they think they can be lucky to make profit before the site colapses. On social medias there are some people saying to be "HYIP masters","HYIP professionals". They think they can know when it's safe to invest on a Ponzi, HYIP scheme.
There are some fail rules they use to say when it's safe, like: Invest on a very new site, between 0-10 days; Look if the number of members are increasing... But it's as you said, it's their own fault, nothing to complain about it.
I do hear some people who said that they are profitable on hyips because they join on early stage, it might possible though but it wont work anytime because most hyips doesnt last long or shall we say they last only on 2-3 days atleast. Roi cant be achieve on that short time thats why most investors would really lost up their money especially for those new people who just joined in.