because ethereum has a smart contracts that can be use to create a token for their ICO, and by the use of ethereum blockchain. it is more convenience to them to use ERC-20 token if they dont have a wallet platform yet, and it soon to be followed. so most of the ICO are base in ethereum thats why, i believe that this basing of all ICO in ethereum platform can be the reason of the huge pump in the future of ethereum. because of the demand and the usage of it world wide. this is the advantage of ethereum on all coins platform exist.