I can see you haven't given it much thought. A first responder arrives on the scene. Victim isn't breathing. Is it a heart attack, a stroke, or drug overdose? People that overdose don't call 911 and say they've overdosed. As for car accidents, if it was caused by drinking and driving would you put it at the bottom of the priorities as well?

When someone needs emergency medical care, society doesn't moralize over the reason. We provide the care first, and then do what we can afterward to see that it doesn't happen again. (Like create a safe injection site.) We've always provided emergency medical care that way, because that's how most people feel it should be done. Your belief about what most people think is just your own erroneous opinion.