I think any habitable planet would be so far out there that Earthlings could never get there. They’d have to build a network of space stations, and by the ttme they reached the planet, some of the space stations would have failed, so they’d have to start all over.
The stars out there are so far away and many of them cannot be used for navigation. So why would God create them?
We can certainly speculate about it. God does nothing in vain so they have a purpose. But that purpose may have nothing at all to do with our current physical reality. I'm a firm believer that the existence of the physical universe is a shadow of the real reality which exists in a realm that we can only describe as "spirit". Perhaps there is something going on in the spiritual realm that does or will involve these. But for now God created life here and his purpose is to bring many sons and daughters to glory.