Joshedog: I'm not sure what they actually do for the club. Are they virtual dollars that add to the wealth of the club
No.
Today, there is no wealth of any CC, and there are no virtual dollars.
"CC earnings" is not more than the summation of all member's earnings which represent a part of previous income but no current assets. The "currency" in WGTland is "credit". Any representation as $$ is undue because the T&Cs state, "credits have no monetary value". Repeatedly, WGT has declined to give any reasonable public explanation of the unexplainable credit => dollar conversion which they perform. Nevertheless, huge "$$ earnings" are shown on the front page.
Joshedog: do they perform some other function??
Introduced last summer, they added a new grinding element to the operation of CCs, "use (&buy) passes to achieve benefits for your CC which mostly have no credit value". You'll find the benefits in your "CC homepage" on the game client. IMHO, there's nothing of any worth for a CC above level 6. The most valuable items in this context are the passes offered in the Pro Shop - valuable income for our host.