That may be a reason why, but far from the only reason why, Heroku is more expensive than a cheap shared hosting provider. Heroku provides a lot more than just

That may be a reason why, but far from the only reason why, Heroku is more expensive than a cheap shared hosting provider. Heroku provides a lot more than just hosting files and running server instances. They provide all kinds of value-added services in deployment, logging/monitoring, security and performance auditing, package management, git integration, database choices and plugin apps, etc etc.