Just to top it up. The theme is free. You can download the full theme on WordPress and get started. No strings attached.
However, if you want to add extra functions you can choose to buy the add-ons. At the current price the add-ons are cheaper than many premium themes I have bought and don’t now use. So, to me, the add-ons are well worth it. Not just for the added functions but in order to support the theme developer and keep the theme a project he continues to work on.
One downside of a free theme is the lifespan. Theme developers have bills to pay too. So a free theme will only get so much time and attention.
The way GeneratePress works is actually quite smart. You can choose the free theme and do your own customizing. If you want to keep it completely free you do your own work. That’s fair enough. Along with the free theme you get the benefit of a premium theme due to people who are paying for the add-ons because the theme is supported by the community.
One other thing which I looked for was how long the support lasts. I won’t buy a theme which asks you to pay for it and then only gives you one year of updates. In a sense it’s not terrible because I have tended to become dissatisfied and changed themes in that time anyway. But, I rate GeneratePress as one of the top three themes I’ve ever used since I began online (before WordPress existed).
Whether you technically consider GP a free theme or not – it is a great theme to have and I have no problem making the one time payment to have the extras.