Despite the common misconception, there is actually no general legal requirement that corporations must act to the benefit of their shareholders. Rather, United States law holds only that the company act according to its charter, which may actually have practically any terms the founders see fit. There may be no terms, permitting executives to have free reign over the company, or there may be very restrictive terms detailing precisely how the corporation is to be run, which is particularly useful for incorporated charities.
With that out of the way, why should there be any question about giving away anything for free? I can't recall any large company whose marketing department didn't get a wide variety of samples or freebies to promote the brand. For anything with an engineering department, the offer to make an expensive system work with other expensive systems has been a common sales tactic. These ideas are not new or questionable at all.
Also falling into the "not new" category is Microsoft's ongoing strategy. For the last two decades, Microsoft's primary business model has been to attach their products to existing business dependencies, encourage their use (forming new dependencies), then drop support for the original dependencies in favor of their own new products, leaving their own product as the only upgrade path for a now-locked-in customer.
For several years, Microsoft has clung to a few bad decisions (most notably ignoring the Internet until it was too late, then ignoring the business need for easy provisioning), leaving room for open-source solutions to grow. Having now completed their compatibility phase, Microsoft moves on to encouraging their products' use. A low initial price tag helps that effort.