ETF's also serve a different purpose - they are FUNDS. As a registered fund certain investors can use them where they can't use futures. Specificlly, many financial advisors are only allowed to purchase mutual funds (40 Act) ETFs and stock - but no options, futures, etc.
Also, IMO the only difference between a 40 Act Fund and an ETF is the ET part - these things are simply mutual funds with intra-day liquidity. There is nothing bad about them, only people who don't know how to use them, dont' know what the investment objective of the ETF is and people who are in over their head trading leveraged products.