They don't (at least, not in peace time), but the US government does. They also buy cars.
Also the concerns of the average consumer aren't a really good barometer for what should be legal. Most consumers gladly sign up for services that violate their privacy, because they don't understand the consequences at the time of purchase. Also people are pretty bad at estimating risks of unknown certainty even when they do know about them. If 'buyer-beware' worked, there would be no need for consumer protection law... but this segment of the law has originated from necessity.
Also the concerns of the average consumer aren't a really good barometer for what should be legal. Most consumers gladly sign up for services that violate their privacy, because they don't understand the consequences at the time of purchase. Also people are pretty bad at estimating risks of unknown certainty even when they do know about them. If 'buyer-beware' worked, there would be no need for consumer protection law... but this segment of the law has originated from necessity.