IEOs are just well-disquised scams, that's all.
So they pay a fee, you buy their tokens and....what guarantee do you have those tokens will be worth something? None!
But you fall for it because the useless token is already on an exchange and you feel like this gives them some kind of legitimacy. It doesn't.
I agree completely with your observation and i am sure it will be a new form of scam projects with the help of exchanges and all they need to do is to pay the exchanges initially and then they could collect a shit ton of money and then pump the coins for a while and dump everything in the market.
Just because you know the team, you know where their office is, they are listed on an exchange, they are paying articles to promote themselves is not a guarantee it will not turn into a scam. Remember bitconnect?Centratech? How would have an IEO saved you from it?
Scams come in different form and there is nothing you can do about it and that is a fact, the scammers will also improvise with the trend and in the next two years we will talk about billions lost in the IEO market because of scams.