I can relate to your worries. But i think they way they built Steem and Bitshares might tell us something of their character. Nevertheless, it would be better if they explained what they are planning to do.

In my opinion if you truly believe in your new platform it is alright to want some of the value. But it might be better to be honest and exact about it to people wanting to participate in your ICO. I mean if they want one million (random number) EOS for themselves because they think they earned it that could be okay right? And if it's not potential investors will behave accordingly..