Forgive the long comment, and this is very US centered and doesn't apply to every area in the US. EMS systems vary broadly between states and even municipalities within states...

To put some of that in perspective:

• A new ambulance costs about $250-$400k depending on the type.
• The heart monitors we use are somewhere in the area of $10k-$25k a piece. That's ONE piece of the equipment that we use, and they need maintenance and replacement every so often.
• There's all the other equipment, and restock of medical items. Even if something doesn't get used it has to be on the truck and has to be replaced when it's outdated.
• Fuel is expensive. The last agency I worked for spent about $400k - $500k a year just on fuel.
• There's insurance - auto insurance, liability insurance, workman's comp, etc.
• Keeping an EMS certification active requires ongoing continuing education credits. We take classes constantly to stay current and to be able to renew our cert, which in some states costs money just to renew. I've spent hundreds just to be able to work, both in con ed classes and certs. Some agencies will help pay for this cost, and many provide free con ed classes for their providers. This costs money.
• There's building costs, rent, electric, etc.
• Ongoing vehicle maintenance (ambulances break a LOT)
• administrative costs, and so many more I haven't listed

And that's all before you get into paying anyone for their work. You aren't paying thousands of dollars for YOUR ambulance ride. You're paying for the fact that the ambulance existed to respond to your emergency in the first place. Many agencies don't get taxpayer money, and if they do, it's minimal. My last agency had townships paying them $2k a year to provide 24-7 ambulance service with paid providers. That doesn't even cover fuel, let alone anything else.

Is it absolutely bullshit that people should have to be bankrupted to pay for an ambulance bill? 100% No one should have to worry about money when they're having an emergency.

If you don't like it, advocate for a municipal tax. If every household paid something like $75-$100 a year you could have the best EMS service with well trained, well paid providers using the best, most up to date equipment available and you would never have to worry about an ambulance bill. The places that implement those taxes generally either don't bill at all or bill insurance and only take what insurance pays them, there's no balance billing of the patient.

But no one wants extra taxes, even if it could save them thousands of dollars, and for some reason people come out and support funding for the fire departments and the police departments and no one wants to advocate for support and funding for EMS, so instead you get this mess where EMS is somehow expected to hold itself together and be a profitable enough business to self sustain. You end up with a system where providers are underpaid, have to work 70+ hour weeks to survive (and thus are incredibly burnt out and exhausted - you really want a provider who has worked 70 hours in 5 days on 10 hours of total sleep making life or death decisions?), the good providers head to places where they can get better pay, the equipment and ambulances are old and being held together by sheer will of the providers, and patients still have insane bills.

Patients should not fund EMS. Government should fund EMS. It's a service, not a business, but under the current system in most places, it has to be a business if you want to be able to call 911 and have someone there to respond.