Your strategy will work just fine... until the "rescue" rider gets a flat on the way to the car.
What's not "realistic" about saving yourself 10 - 25 mile walk with a bit of kit that'll cost you maybe $20, fit in a sock, and weight less than a pound?
Speaking for myself, I wouldn't risk a lifetime's worth of "I told you so" from SWMBO when such a minor investment would prevent it