That was the peak, the summit, the pinnacle, the apex era of "independent promotion" where record companies contracted out some promotional activities. This allowed the record companies to be "clean" at a time when more and more labels came under fewer and fewer international consolidators.When I programmed in a century that started with 19, the songs that made it on the air was highly a radio/record collaboration that featured record companies offering “promotional” opportunities such as concert tickets, music product, etc.
So the independents were still free to send a goon to "adjust" a PD that had not fulfilled a promise. And they did things like providing the station stickers or van wraps or boxes of tees in compensation for being part in the promoter's "advisory panel" or some other artificial construct.
"Play my record" became "youse betta play my record". And the advent of FedEx and UPS overnight gave us coke-o-grams, the envelope from a record company with no record release inside. And accounting wondered why boxes of single edged blades were being ordered every few months.