[DTV]

I'm not really sure it would cost less to produce in London. Other than the travel costs for non-Salford based presenters (which aren't huge, and there'd still be travel costs involved were they presenting in London), there is no extra cost to it being produced in Salford. In fact, overall staffing costs are likely lower as I imagine that, like many employers, the BBC pay London weighting. Per person, again not huge, but for entire production and studio teams is probably quite a decent saving.

You say there's no need for it to be produced outside London, but the same is true in reverse. It has never been easier to produce a news programme outside of the central newsgathering base - VTs and any other assorted London-produced items can be sent over instantly - so it's not like it impedes production in any meaningful way. So why not? Especially as it helps the BBC meet out-of-London targets. Ultimately, producing Breakfast in Salford isn't difficult to do, is an easy political win and, as others have mentioned, has other benefits, such as to regional job opportunities.