Debating myself a bit: the reason startups tend to attract fewer scams is that only accredited investors can invest in them. There is definitely something to be said for that!
Generally you're only going to get decent money from bigger names (or at least one leading the round) - and a bad reputation will make it quite unlikely you'll get to play again. This helps avoid many straight-up scams like Dentacoin (lol).
Then, your future rounds of investment are conditional on demonstrated success. Your A can be a bridge round based on traction or a materialized idea. However, your B is generally based on hard numbers.
ICOs tend to get series F/G money up front on a hope and a prayer.
