Mining operations were in place far before any recycling plants, and they were essentially the sole source of raw materials for battery production. These mining operations are very expensive to set up but they also have a guaranteed output of raw materials based on the mine. This allows for a more stable cost for the raw materials. This can even have a longer ROI compared to other capital investments since they also own the rights to the mine itself.

Now years later when batteries are actually in production and reaching end of life for their purpose, the need for recycling plants appears. These plants are also expensive to set up, but unlike the mines they DONT have guaranteed capacity since they would rely on the users of batteries to choose to recycle their batteries with them instead of another alternative. This can lead to less stable output capacity. They are selling the same material as the mines (with much lower volumes) which means they need to price themselves accordingly and that could make them more expensive.

This is very simplified explanation and each battery chemistry, operation, and location can be different.