A billion crickets?
Crickets come in various sizes. Most of them I see are probably about a quarter of a cubic inch. Allowing room to move their legs, figure two to a cubic inch. That would be about 3400 per cubic foot. The Athearn car (early FGCX) is stenciled 4170 CF. That would hold about 14.7 million crickets, loose. Say 12 million to allow them a little more room. You'd need a long train to hold a billion, but even one car would make a racket.
As for why, most pet stores that sell reptiles also sell crickets, as snake and lizard food. They're sold live, and have to be bred somewhere, so why not a reefer full of crickets. No worse than trucking honeybees, which is done all the time, For all I know bees may have been shipped by rail in the past. I'm not so sure of crickets.
As for the dripping water, I'm not even going to listen to that. I've had enough faucets do that live. But why would anyone bother recording an hour of it?