I saw pretty easily how Instagram could be worth a billion to FB, who has a social network and wants to expand their user base / stop competition from rising.

I don't understand how these shares that pay no dividend and give no voting power are worth $24 each. They are basically "SnapChat Fun Bucks." Anyone buying it just hoping another person down the line will pay more for it. On top of that, we know there's a large number of people holding it (employees) that are going to start selling their shares over the next year.

I just don't get how this has any value at all.

Short it if you truly believe the stock will go down. Easy money ;).

I'm humble (and risk averse) enough to admit I could be wrong. But it baffles me.

To be fair, you didn't take into account the difference that $1B was worth between those times. Not just inflation, but the economic situation in 2008 as well.