The scammers wouldn't ask for bank details if they weren't useful!
You can't withdraw money directly with only that information, but I know someone who suffered theft of ID and real money, and that was one of the steps. The rest of it involved (a) phoning the bank (quoting A/c no. of course) and asking for a replacement debit card "because it's damaged, and while you're at it better send me a new PIN too" then (b) explaining to the local post office that because of a messy marriage break up you want post for Mr X held in a mailbox for collection. A week later the thieves have card and PIN...

The sleepy,rural post office were mostly at fault in the above incident, for not getting hard ID, but it happened and apparently it's a common occurrence.

It's aimed at small company directors whose names and addresses are often readily available.

I'm sure there's lots of other ways that crims can accumulate info about people from different sources, which when combined are dangerous.

Anahata