It makes a big difference when developers can rely on help from the DBA. I've been in many situations where I've suggested to a dev that their statements, while they work, are eating up resources and things could be much faster if we changed this or that. Many times the first reaction is "it works, so piss off". I'll demonstrate how a change could knock this many seconds off of something and how much less work a query performs as a result of a proposed change (Of course, people only care about the reduction in execution time).
We you can do this you've not only shown that you can improve something, you have also demonstrated that you are willing to take on this kind of work (an offer not usually accepted the first time). The benefits of this are enormous to both sides. Clearly it is a major benefit to a developer when they can pass on the work of writing things like stored procedures. Now they just call it and how this "black box" works doesn't matter to them because it just works. For the DBA who writes this proc the benefit is that you've kept something nasty from being introduced because you have control of its construction and implementation. Soon the developers come to you first to handle this stuff. Devs are writing code (not SQL) and the DBs are running smoothly.
DBA may mean don't bother asking to some, but I suggest if the answer to a request has to be no one should try to offer another option that works for both sides whenever possible. Sometimes the answer will be no and the requester will stomp off unhappy. Perhaps this is due to a company policy, a limitation in software, or even just a plain ridiculous request. Unreasonable expectations or a feeling of entitlement does not make someone right. There have been times I've had to OK something I really hated, but a business requirement has more weight. I try to mitigate what I hate so the business need can be met and I can be a bit less unhappy about how it is met.
Now, if a company has a culture of not allowing DBAs to do any dev work, treat one group as better than the other, or even just discourage direct communication then that is a major flaw in how that business is run. Don't dare make eye contact with so and so isn't the right way. This happens all to often and it is a major cause of this divide. If you constantly tell someone they are better than so and so they will come to believe it.