I'd have to wonder if that expectation of sending anything over $3000 was just in the KHs that you've gone to..because when I was accounts servant in a congregation in Ontario Canada that was never the case.
We had boxes labelled specifically for "congregation" (our own KH expenses), "world wide work", "kingdom hall build fund" (for construction in other parts of the world), and a fourth one once when all the congregations were raising funds to renovate the shared KH.
Each congregation had their own accounts with money fluctuating but I also maintained a second and a third account that had joint contributions. Those other two easily were over $11,000 CAN for months on end before major renos were made.
The congregation account was barely over $2000 because most of the dubs were cheap skates. These were not poor starving people. Most were middle class and a few were well to do. It was mostly two families who repeatedly bailed out the congregation from failing to meets its share of expenses because at least 60% of the people were not putting anything from what I saw. I put in my small amount of the KH itself.
The WTS though could go to hell and I loved to over order mags and crap like that when I had that stint. They didn't keep me long on that one.