Exactly. At the most recent CA I attended (physically not mentally) the expenses were around 4k but 4k more went to the WWW & kingdom hall building fund. Interestingly, enough was collected on day 1 to cover the operating expenses but it was the contributions to Mother that resulted in the deficit. Also, the money sent to the WTS was more than at the previous CA (they were crazy enough to read last years stuff and I actually paid attention!)
I think the business meetings varied from circuit to circuit. The one I was at the longest made the line item information available and read it at the meeting (large categories - operational expenses, CO expenses, DO expenses). Remember, the circuit pays for the COs housing (usually an apartment in a KH but still has utilities and a set amount per month for upkeep).
Usually, those business meetings were attended by half the circuit elders and the object was to get out as quickly as possible. Read item, discussion (pause for about half a second), ok then do we have a motion to approve, "so moved", second?, "I second", all in favor? meeting dismissed.
Edited to add: Just remembered that several years ago, the circuit elders decided to send a percentage of the surplus (I think maybe 90%, can't remember the details) to the WWW. They had done that historically and that really makes sense (save some for the circuit account and just give the rest to HQ). Well, apparently something changed one year when the assembly overseer told the elders that he was informed that was no longer acceptable and that the elders had to vote on the contribution to the WTS at the business meeting (held Sat lunch). Several objected (including the assembly overseer) saying that the expenses were being driven up unnecessarily. And, it was "suggested" that the circuit donate XX which I found out later was the amount per publisher that Sir82 mentioned. Who says the WTS doesn't tithe?