+1 - Air evacuation is almost never covered by standard health policies in the US. If you are an organized tour such as a cruise, the cruise line will be able to coordinate air evacuation, but won't cover that cost.
Air ambulance from Asia/Africa back to the US can cost $120K or more and if you are travelling on your own, can be difficult to coordinate all the clearances some countries require.
If all you require is a few sutures, that is fine. But, if the nearest surgical center you trust is half-way around the world, spending a bit on a policy is well worth it.
Add to that other associated expenses, such as being "grounded" in a hotel for a couple of weeks or having a spouse or friend who needs to stick around to monitor care, and the costs can become overwhelming to even the well-off.