The fact that this company is fast approaching $1B without sustained profitability demonstrates the monstrosity the pharmaceutical industry has become. No wonder hospitals get away with overcharging for services and supplies by about 8000%.
The goal of Exparel, Pacira's leading product, is to reduce hospital expenses associated with the treatment of post-surgical pain by replacing more expensive traditional treatments. Hopefully this product will help both hospitals and their patients save money. Perhaps this is driving the valuation.
Actually the goal is to avoid opioid use which isn't that expensive, but the addiction problem and side effects are. So, you're correct in a way, but Exparel is not cheap. It is fairly expensive. Much more expensive than generic opioids, but I would lay claim that it is worth it.