Right now, probably so. Though, to AWS' credit, they've been "diversifying" in developing some of these other complementary services (RDS, Route53, ElastiCache, Search, DynamoDB, Elastic Transcoder). It's getting to the point where EC2 is a good fit for those who want less infrastructure responsibility (and are willing to pay for it).

If RDS/ElastiCache were cheaper, I think it'd be a lot easier to make the case for EC2 for startups and smaller companies that don't need the auto-scaling features. Even as a smaller business, it's a lot better for us to spend a little more on infrastructure in order to avoid hiring additional people to keep us running.