It is not generosity, they hook you in for free so when your needs grow you will stick with their platform and pay. Static sites are cheap to host that is why it is free.
Should your needs grow past simple static sites they are hoping you will use their paid options. This isn't a "you are the product" situation.
Should your needs grow past simple static sites they are hoping you will use their paid options. This isn't a "you are the product" situation.