<10% seems like a lot. If 10% of all seat belts saved lives, that would be a bunch of wrecks.

Careful of the statistics. Depends on how long a car is in service. A car having a wreck sufficient to pop an airbag over a ten-year lifetime is probably not that remote a chance, and a one-in-ten chance of such a wreck over the life of a car is even more reasonable.

Of course, such a wreck for a car means a trip to the body shop. A wreck requiring ejection for an airplane means you get out the broom.

I've worked with a lot of ejection seat companies in the course of spacecraft design. The Russians were also known for building reliable, if a bit heavy, seats. Don't know if they're still in the business.