Indeed. Google is a free service and Google Apps is a paid service, but I wouldn't expect significantly more longevity from the latter just because I'm paying them $x a year than I would from the loss-leader service.
I think it is a bad example because it is probably contributing less than 1% to Googles bottom line. Much easier to cut than if it were the primary revenue source for n individual company.
For exactly that reason it's a really good example of the point I was making: what you really need to know is whether a given product is strategic to its supplier. "Am I paying for it?" is one indicator that it may be, but it's not conclusive
