I grew up reading the Hardy Boys series, and recently decided to skim through some of the newer books to get a feel for the modern editions.  "Modern" may be a bit of a stretch as the issue I'm currently reading, Casefiles #63, Cold Sweat, was printed in 1992.  I think the ghostwriter must be a Parker fan.  The story begins with Frank and Joe starting new memberships at the local gym, the Harbor Health Club.  Wait, there's more.  I'll quote the story, from page 3: 

"Besides, Frank was interested in seeing the new Harbor Health Club.  Five years before, it had been the Dockside Gym, located in the basement of an old warehouse. Frank remembered the place as a sweat-and-strain shop where aspiring boxers worked out." The next paragraph describes how the neighborhood had changed, new owners bought the old warehouse and turned it into an upscale health club.  No mention of Hawk working out effortlessly.

I wonder if a new generation of Hardy fans will grow up to read Parker and think he stole their gym.