With the rate of Bitcoin scam to in the world I today I will say it's cause as a high demand for Bitcoin and the rate in which it appears to benefit than other crypto coins, Bitcoin is more value like and asset it's also used as a payment method in mostly all the website than other crypto coins or cheat coins people sees it as an opportunity, with the high rate of Bitcoin people offer to double the amount of Bitcoin you bought just for you to get away with your money that's the popular scam now website promising to offer you high amount of Bitcoin in return they are all scam just few trading platform are real.
The fact that someone cannot earn Bitcoin easily, as they are most likely offered by scammers, does not mean that Bitcoin or cryptocurrency is bad. We are looking for an income opportunity, but first of all, cryptocurrency should be seen as something more and valuable, and not a way to make money.