We agree, customers are valued and should never be abused or exploited.
I think you must be assuming that we could have done all of those things in v1 and sold it to you at the price you paid... had we added all of those features to version 1, we would have had to charge at least the price of Version 1 + the upgrade price in order to afford to.
We only charge as much as we need to in order to recover the development costs. By starting with fewer features, we are able to offer it at a lower price initially. Then the purchases of the initial version help fund the future updates.
Version 1 was not clearly deficient... It is not as full featured as future versions, but I think there is a very big difference. Many web sites continue to use version 1 without difficulty. The additional features are not necessary for all stores and don't represent a problem with the first version. We continue to fix bugs and do dot releases for any problems with older versions and stand behind those purchases.
We aren't a funded company. We use our profits from one version to create the next, and need to have profits from the next version in order to be able to afford to do a third. If we didn't charge for updates, we'd have to stop making them. We price our products at just enought to make back our investment. The powerstore v1 that you purchased for a couple of hundred dollars cost us tens if not hundreds of thousands of dollars to create, document, and support.
We create a mutually beneficial relationship with our clients where the money they spend on our products goes directly back into making those products better. Yes you need to continually give us more money in order to upgrade, because we need to continually spend more money in order to create those upgrades.
We need to charge for those updates to fund the next round. It isn't a choice we make out of greed. We don't have any private funding, angels, or a huge endowment to allow us to work for free. I hope you can appreciate the difference between only charging enough to stay in business and being abused and exploited.