A little history....
In 1998 we started an Internet Department that was centralized and served 9 different locations. When a deal was sold that could be sourced to the Internet Department the commission was split between the sales agent and the Internet Department.
I sold cars during those days and I recall how much I hated the Internet Department. "You mean to tell me these 3 people down the street just told a customer to walk in at 3:15 PM today and I just spent 5 hours negotiating and holding their hand for a mini deal? A mini deal that is now being split with someone who didn't do crap!!! F^$@ that!!!" The sales floor ended up sabotaging the department by hiding deals from them. Managers actually helped. It was an unfair pay plan. But it made sense from the 10,000-foot-view.
The department was dissolved around 2000. In 2001 my GM approached me and said "Alex, you're in college, you're young, you can type - can you handle these Honda leads I'm catching a lot of hell over for not answering?" That's when I got involved in the Internet business. Over time we found a need to export things I was doing at Honda to other stores and in 2004 my current position was created.
In 2004 we started our "re-newed Internet Department" evolution with Internet Sales Coordinators (most other dealerships call them Internet Sales Managers). With multiple rooftops I quickly discovered that a few of these ISC's would only work if I was standing over their shoulders - the stores had no desire to manage them. In some cases these ISC's were splitting deals with sales agents, so they were hated.....and I think that had a bit to do with the managers' attitude toward managing them.
In 2005 we turned our Toyota store's Internet Department into a hybrid BDC. It worked so well, that we consolidated the entire company into one BDC in 2006.
The real trick was not to repeat what our last centralized Internet Department did, so we charged the BDC to the advertising budget and did not do anything to effect a sales person's commission or unit count.
In September of 2008 the economy went to hell. We went through lay-offs and broke the BDC up to become ISC's in the stores again. We thought our GM's and sales managers were better versed and educated (and they were) to better manage the ISC's this time around. But by January of 2009 it was obvious things were being neglected. All the strides we made in the CRM were gone, people were demoralized, everything I built was disappearing - it was a sad time for me.
By March of 2009 the signs were so clear that we put everything back to the way it was before September 2008.
Summary: Why do I tell you this?
Mainly because it is a little after 6:00 AM and I ramble before I have my full dose of coffee

...just kidding, there are a few lessons to be learned here.
1. People are dumb and lazy by nature.
Jeff and I were reminded of this yesterday after a little April Fools joke
2. There is a deeply embeded culture of "wait for a customer to show up; don't go get one" that has infected our sales floors. I'm talking about our entire industry.
3. Don't mess with a sales person's money. If they perceive you to be taking their money, they will rebel. No matter how worthy or rational the cause.
4. Don't expect a sales floor to get anything done beyond working a customer in person and the other traditional activities. Over time, this has changed, but it is a slooooow change.
To answer your question
We don't need to protect our BDC because they don't "take anything away" from the sales floor - they add to it! Sales agents and managers now view them as a huge assistance that allows them to concentrate on the things they like doing. The only issue we have is trying to stop a sales agent from entering a duplicate customer and fouling everyone up by putting us all on different CRM follow-up tracks with that customer. It took me over 10 years to learn that this is the way to do it. It will take me another 10 years to keep pushing the sales floors toward breaking their "wait for a customer to show up; don't go get one" culture.