A national PR cost less than $1k; regional, a fraction of that. In either case, the PR is posted on Yahoo! and other internet sites, making it effectively a fraction of the cost. Assuming that is the reason... there are better ways to save. Or maybe they just want to keep a low profile.

Having the Q&A emailed is better for the company, as they have more control over the questions--and their tongue. (Remember the heated discussions in the past?? Not much control they had at the time.) There are plenty of companies that continue to open their lines even though no one's calling. They can have both, but choose not to.