1500-1600 entities listed in directory of trade associations. The more competitive the market, the more likely companies will have PR people. Team should appear to be a good citizen of the community. Prof. Bivins gave the example of PR personnel getting a NY Times front page mention of the 50th anniversary of Teflon. Product promotion is often very subtle.
Media coverage is more believable, credible than direct info.
Fact that you do not pay for publicity also makes it more credible. Anybody who lobbies represents a special interest. Person keeps track of all regulation coming down the track. Public affairs personnel may perform both of these jobs. Fund raising and membership drives, e.g., public television and radio drives, join for money.