This is the same group. The amount of experience does not determine the classification. It's the intent. If someone buys Powerstore for their own website, then they would be an end user, not a developer.
It shouldn't be. But if someone sells a full blown store for $200 it becomes one. Why pay a developer more than $200 unless they can provide more functionality than the $200 store? You've just raised the bar for all developers and increased their costs at the same time.
The ISP could not compete with the developer at all if you didn't sell a completed solution. The developer can no longer make a profit from your solution because they start at the same price as the end-user.