Most of the ICOs I would consider a scam are these fly by night token ICOs. Sure, there have been a few ICOs that offered token payments that were legit but for the most part like Cryptodevil said these guys have a whopping 200$ at most wrapped up in an idea and have no intention of following through on promises. They are offering tokens basically because there's no risk to them this way.

A team spends 100-200$ and gets some wallets made and tokens produced. Then they launch their ICO(paying bounties with tokens) and if they don't make any money they can still pay out tokens and only lose the 200$ investment. Who cares if it gets listed or not in their opinion. If they don't make money obviously it's not gonna be listed. I get contacted by at least 5 companies a week that have this strategy going on.

As far as making ppl pay a 1btc listing fee, that wont exactly solve the problem completely as others have stated. A company can spend 1btc 100x in 6 months on 100 campaigns. As long as they make more then the 1btc fee they paid, they still profit and still spam the fuck out of the forum.

I personally do not touch the token campaigns(least not very many unless i trust the team), but there are plenty of new managers out there willing to take on any project offered.

My suggestion to go a little further than others suggestions would be to not allow bounty campaigns period. If they want to do airdrops sure, but all campaigns must pay in an asset that's listed on an exchange in order to be using this forum+the 1btc list fee.

I doubt that changes much either but i'm sure it wouldn't hurt