You wrote: "casual users." Did you mean: "free hangers-on?"

This blog post sounds like the perfect example for why services need to charge up-front. The author acts like they deserve a greater level of service than "none," when the high cost of this type of user (vocal, complaining, sense of entitlement, unlikely to pay or they would have bought Balsamiq in the first place) is exactly the reason that Mockingbird is shutting down all the beta-created projects in the first place.