This research from the late 1990’s shows the sections of a local newspaper that get the most readers. Working on the baseline that most editorial is read by all, only (paid for) advertorials got very slightly more readers. The rest of the newspaper’s readership slowly declined, ending with the advertising pages, which attracted less than half of those who read the editorial.
Other research also shows what type of editorial get most readers – these are: announcements, horoscopes, the problem page and letters page.
Back to the original question “will your press release get more readers than paid-for advertising?” – possibly, if you can get it printed on the right page. Alternatively, write a letter; with some careful crafting, you may get a subliminal advertising message in there.
(Article source: Welbeck Golin/Harris Communications Limited/The National Dairy Council/Ros Jay & Financial Times Professional Limited)