In Asian countries, people needing treatment is an opportunity to improve lives. In the US, people needing treatment is an opportunity for someone to make bank.

Pretty sure most of the post-exposure (PEP) cost is from the immunoglobulin, which is also why antivenom is often so expensive because it is also often immunoglobulin based. A synthetic alternative to immunoglobulin should bring the price down and make it easier to store/transport.

Pre-exposure (PrEP) for rabies (a vaccine) is more expensive than it should be due to lack of economics of scale and the typical American medical pricing inflation. That's not unique to rabies, it's just how vaccines are allowed to be priced in the US.

My understanding is poorer rabies prone countries do not even attempt PEP for rabies due to the cost, they really rely on broad PrEP immunity.

PEP is always going to be more expensive than PrEP, because transplanting a vaccinated animal's immune response proteins is a much harder thing to do than getting your body to make it's own.