I look at the DBA roles as generally the production or support role. Then the development DBA's and a small chunk of QA DBA roles.

The support DBA works on the day-to-day applications to make sure they are up and running. If the DBA works for an end user company he's going to interface with the SW production company to find out the cause of the error. If the support DBA for the SW company the responsibility is to figure out if the error was caused by a SW feature or end user error.

The dev DBA does the building of SPs, functions and such to automate the process.

The QA is the in-between that doesn't let crap get to the end-user.

Where the problem seems to come in is that you have a bunch of developers that think it is faster to grab 3K rows in a hundred column table of millions and process it RBAR rather than ask the DBA "Can we get these 25 rows by feeding in these parameters."

I've seen it done in the past, and I'm sure I'll see it again.