Can't speak about 1). Can't speak about 2) either; but HNers told me Apple did extensive testing to ensure pods would not fall while being in your ears (the physics hints that earplugs fall mainly because of wires).
Still 1) is a good question. I thought they came with a tiny casket, so they wouldn't fall out of your pocket like that. Still subtle when you remove them from your skull.
They come with a charging case which looks to be about the size of the little plastic spool-box of dental floss with which some here might be familiar. It's not very large, but shouldn't be small enough to easily drop out of a pocket without being noticed, either.
I'm not sure what I expect with regard to staying in ears, though. They appear to be closely modeled on the wired EarPods, which in my experience don't reliably stay in the ear on their own, to the point where they are best worn with the cable wound around the crease of the pinna - both for strain relief, and so that they're easier to recover and less likely to be damaged when they do inevitably pop out.
Still 1) is a good question. I thought they came with a tiny casket, so they wouldn't fall out of your pocket like that. Still subtle when you remove them from your skull.