Many projects conducts IEO on different exchanges to collect more money for development.
Well it's really necessary if they really wanted to continue the project and they don't have enough funds for future developments. It's also a nice chance for us to grab some opportunity for those kinds of projects.
It is necessary that it will be demand in the tokens, but if the project conducts a lot of IEO in different exchanges and sell a lot of tokens there are a lot of tokens but no demand in tokens.