The tragic part of it all is how Prowse's relationship with Lucasfilm soured over the years. During the making of Return of the Jedi he was accused of leaking details about the movie. By all accounts he was innocent but Lucas seemed to harbour a grudge against him ever since, even banning him from official Star Wars events.
Another kick in the teeth is that Prowse was among members of the main cast who were entitled to residuals from the profits of Return of the Jedi. Due to "creative" Hollywood accounting, despite grossing close to 500 million on a budget of just over 30 million, on paper, the movie never made a profit.