I'm using Europamine since 2018, when they started to sell hashpower, I don't think it's a scam because usually scam don't last 3 years.
Sunmining, Auroramine, Hashmonster and many others scammed in less than 2 months, Hashflare, Genesis, Europamine, Hashing24 are up, so not all services are scam.
Few week ago I've seen sha256.io, but the have price very very low and I think could be a scam.
If buying bitcoin costs me less than doing a mining contract, then I buy bitcoin, but if I have a mining contract that doubles my capital in a year, then I go mining.
I explain: if I invest $ 100 in a cloud mining service and the forecast is that after 12 months it has become $ 250 (like now on Europamine.com), I find it interesting.
If at the same time, investing $ 100 I buy 0.002 BTC but after a year, BTC has not increased by anything, I always remain with 0.002 BTC
I seek profit, sometimes cloud mining is better and sometimes it is better to buy BTC directly, it depends on the price of BTC and the cost of hashrate on cloud mining.
Cloud mining services are either:
1. A scam
2. Unprofitable and a total waste of money
Think about it: if you have the hardware to double your capital annually, why the heck would you rent it out to other people for cheap? Logically, you'd take advantage of that opportunity yourself.
P.S. Bernie Madoff's ponzi scheme lasted more than 5 years.