Why do so many Google employees appear to plug their stuff nearly every day?

Good or bad or other, Google seems to be the only company that engages in this sort of cheerleading on HN. Does anyone else think this is a strange state of affairs?

If it's a new service announcement, there will be an army of people to answer questions and solve support problems. If it's a story about a competitor, there will be an army of people prodding you to try Google instead.

Even if this isn't an organized part of their media strategy it still smells a bit off, no?