I'd probably do this too if so many people were willing to let me hold their fiat for 10 days before I give them what they want to buy.

The 10 day waiting period will eventually take coinbase down, insider trading or not.

I'm not saying they have 100% malicious price manipulation intent either.

Last week, my bank charged me an overdraft fee in error. They told me it would take 10 days to credit my account with the money they erroneously stole from me.

I wonder if they are sitting on my money in the vault, not using it?

Or if they have used the time "holding" my money investing it - and will pay what they owe me out of someone else's held funds while they wait 10 days to get it.