First, HCI just doesn't have many grassroots members - a fact openly admitted to by its sycophants at the Washington ComPost.
Second, HCI's Web site just doesn't get that much traffic; it is rated 107,854th of all Web sites! The nominally-separate "Million" Mom March Web site is even far-lower-ranked.
It is difficult to make significant profit on "affiliate programs" - as many of us who are webmasters know! Maybe HCI gets enough from its "affiliate program" to pay its ISP - but it sure couldn't make enough to pay even one full-time staffer on a site ranked so low.
Also, look at what HCI's "affiliate program" sells - computers, dresses; this is all the kind of merchandise most people either prefer to "test-drive" at the local mall or just order directly from the merchant itself. I doubt if HCI makes enough to pay its ISP out of this.
HCI recently begged its few actual members for cash, remember - saying that it was in a financial crunch? My gut feeling is that HCI is financed by grants from leftist foundations; HCI has said it has received major gifts from individual leftists within the past year (one a bequest from a well-known newspaper cartoonist).