If these sites just go for some verification before promoting these scams, it would be very good for the visitors.
This is the reality, because people know how much money in the cryptocurrency ofcourse a lot of people will do shady things to have a part of it.
The sad truth is in advertising industry as long as they are paid enough to advertise a project they will advertise it event it turns out into a scam.
What is happening is that, most of the time, advertisers are the bounty hunters as well. I became a bounty hunter before, and I strictly not supporting scam projects and I will never knowingly support bounty projects. Most of the time what is happening is that they promise good amount, not that high, but just in exact, so you will believe the project because the particular scam are those that promise something that is too good to be true. In this case, you knowing the project is legit will turn out to be scam.
The lesson here, you cannot determine now, what is legit and good unless you haven't really tried and proved it. So we really need to take risk in order to earn profit while not supporting these frauds.