Here is a bit about the event that Martha talks about in the DVD commentary:

Goonies was filmed in Astoria during the fall of 1984 while several City Hall employees were developing a city-wide safe alternative to trick-or-treating.
They were able to arrange an "autograph" party with the Goonie child stars in conjuntion with this first Great Monster Bash.
All six stars, decked in Hollywood-style Halloween costumes, came to the lobby of the YMCA located on 12th and Exchange Streets for their first autograph party as Hollywood stars. Crowds packed the small lobby ao tightly that no one could move. Even with a bull horn, instructions could not be heard over the excitement of the multitude of kids. Eventually, the adult stars volunteered to come to help control some of the crowd by signing autographs in another room. Thanks to the efforts of the Goonies, the Monster Bash was a huge success and has continued annually since that time.