Moreover, Google makes money from each mailing list (for example) by displaying ads. The revenue that they bring in from each list is pretty small; the key to their income is the huge number of lists that they support. So losing even 100 lists every week, I have to imagine, wouldn't put much of a dent in their income.
By contrast, the overhead and cost associated with hiring, training, paying (salary + benefits), and supporting an employee are pretty high, particularly when you're offering a commodity product competing with other commodity (and free) products.
From a user's perspective, it seems insane for Google to ignore the business opportunity associated with support. But I have to believe that they've run the math, and that ticking off a number of their customers is cheaper than charging them for decent support.