The scammers will always flock to where the money is. Previously, it was MLM and HYIP schemes, Nigerian 419 scams, etc..
As for the policing of ICOs, I'm not sure that will do any good. With freedom also comes a hefty dose of responsibility.
You want decentralization? Fine! However, everyone have to do their own homework and research. You can't have it both ways!!
Let the scammers do their thing, and if gullible, ignorant people give them money - well, that's their problem.