> for startups probably not worth the ROI.

I definitely agree. That said, I think people seem to forget something.

Amazon says: "your instance may go down and if it does we may just terminate it, reclaiming your ephemeral disk. All data not on EBS will be lost."

Every other host (at least implicitly) says: "your instance/machine may go down, we will attempt to recover your data. The ability and speed depends largely on why the machine went down and whether we run RAID/etc on the machine."

I've waited weeks for a disk repair from very well known/regarded non-Amazon hosts. Redundancy is needed everywhere, not just on Amazon. Bare metal still dies, controllers flake out, networks go down.