Cloudmining and hosted mining are really famous because you don’t need coder skillz to set up your miners. Setting up miners is simply done by someone else.
Cloud mining is scam, no doubt about this mining type. If you can use Cloud to do Bitcoin Proof of Work, Bitcoin network would be very weak and not as secured as it is. This blockchain is a strongest one in hashrates and security as well as its clean history of no 51% attacks so far.
About scam Cloud mining.
Cloudmining 101 (ponzi risk assessment).