If the Ad Council's name is significant as more than a reference, it could indicate either that it was actually an alliance of sides like the Royal Crown Coalition rather than a single side, or that the side was governed as some form of oligarchic republic (perhaps with the Overlord selected by a council of senior warlords and casters), rather than a monarchy or dictatorship as most sides are. It is unknown how the rules for such a side would work in practice, if it is possible at all.
Real World References
The name of the side is a reference to Ad Council, an American non-profit organization that distributes public service announcements on behalf of various sponsors.
Since the Ad Council historically promoted the Rosie the Riveter fictional character, to promote the employment of women during World War II, as well as the famous "loose lips might sink ships" campaign, a historic scene might have some allusions to these campaigns. Likewise McGruff the Crime Dog was a part of another campaign of the Ad Council and may be seen in the future as a unit type or a City. The publicity around Nancy Reagan's War against drugs included the "just say no" campaign with Ad Council producing PSAs about frying eggs and brains. It's not clear how a campaign "Friends don't let friends drive drunk" can be tied into the Erf story, but it wouldn't be surprising if Balder does so in some way.