The term “Pipe Dream” tends to mean either “Hollow Dream” or “Dream made of smoke, or from smoking a pipe”. I would suggest that dreams may often seem unrealistic or too fanciful, but that does not make them unworthy dreams. Even the oddest dreams can be goals for real projects. We use the term “Pipe Dream Pub” ironically aware of the negative connotations of the name. The fact that it may someday be achieved makes our use of the name sarcastic.
May people use the term “Pipe Dream” for various projects, businesses, and operations:
Public Radio Show “Pipedreams” (first aired 1982)
Government Justice Department / Law Enforcement Program “Operation Pipe Dreams”