Because the degree of randomness is much smaller. Don't get me wrong investing in an idea with no tech is just bad business but investing in many of the cryptocurrencies with proven real world applications is a no brainer.
You are also investing your money, just with higher risk and lower returns. That is what is wrong with what you are doing
Sure there are many cryptocurrencies that really provide not only real world applications, but also tremendous value compared to centralized competitors, money transfer being the first one to come to my mind.
In fact, among all of us in crypto universe, many people do extensive research and elaborated investment.
What I wanted to point out was how much money is blindly going into projects with nothing but a whitepaper and a couple posts in bitcointalk announcement section, making millions through ICOs.