It's not a tactic but an observation. I don't use any tactics here - just expressing my views.
Indeed, this really should be considered as "dumping" (price policy). Why do you think Google gives away free site search and other stuff? This is done not so much to get 0.001% higher share than they already got, but more to kill revenues opportunities for wanna be search engines.
And then what? I read all the time on this board about devastating effects on sites when Google changes algorithms or whatever happens and sites lose lots of traffic, this alone should make any reasonable person support competition and resist the monopoly no matter how attractive it may be at the time.