No, people are idiots. Healthcare should be available to everyone so that doctors can diagnose them properly and prescribe the drugs. It's not even about abusing them but the loads of people that will kill themselves because they have no idea how to diagnose correctly or do not care which dose to take.
Then again, we might be a lot better off with stupid people killing themselves. Soooo... hell yeah strong prescription drugs should be available to anyone!
If you demand respect or gratitude for your volunteer work, you're doing volunteering wrong.