When you attack an individual because of the place s/he chooses to work you take the "Let's all protest the activities of Big X" down to a personal level. I'd be horrified if I woke up and found a large group of people protesting in front of my house because of who I work for. Reading this message, I instantly put myself in that employee's shoes and instantly became hostile toward the organization arranging this. I made a second near-instantaneous cognitive jump, and this is the most important part, to completely disregarding whatever legitimate (or otherwise) complaints this group had and to assume that I should give Google the benefit of the doubt. This may be just me, since I avoid politics at nearly all costs, but despite the fact that I'd probably agree with this particular groups gripes, I can't make my mind see them as anything other than a waste of perfectly good oxygen.
Did they change my political opinion? Probably not, but they were more likely to make me against their particular cause than for it by this action.
Can anyone see anything of value that they might have gained in the process? I'm finding it difficult to come up with anything...