Why isn't it FREE as 'Advertised'?
Are you upset that the add-on was 'advertised' as FREE and then you find out you need to pay for the full version? If so, we are upset too!!! Few people realize that the add-on developers don't have much control over the blue 'FREE' button which shows when you search for an add on.
As developers we can either have a price showing or the 'FREE' button. If we opt for a price, this means that users like you would be forced to buy the add-on just to install it and try it out. If you don't like it you would loose your money or have to go through the process of getting a refund. We don't believe this is in the public's interest to make you pay for something that you just want to try. Therefore, you'll notice that all Google Add-on developers will mark their add-on as free and then ask users to pay for the full-version later.
We also hope you understand that it takes a lot of time and money to create and maintain the add-on. The license paid covers a fraction of the costs yet it can save you tons of time. We hope that you can support us in keeping the add-on up and running.