Bitcoin is great for prospecting, laundering money across borders, and scamming gullible people. It's also easier to hide a stash of stolen bitcoins from the authorities for after you get released from jail than it is to hide a stash of actual money. Bitcoin is certainly no alternative to actual money but it's not entirely useless.

I think these Twitter DMs only does the scamming the gullible part, as you need to pay to use the feature and this is scamming people into thinking they're paying for secure messaging.