The “problem” of induced demand

Source: EconLog
by Scott Sumner

“Opponents of a new and bigger bridge connecting Vancouver, Washington and Portland, Oregon claim that it would cause more people to use the bridge. Supporters of the project assume that there would be no increase in the number of cars crossing the bridge. That strikes me as kind of odd. Consider the following analogy. A movie theatre is so popular that it often completely sells out. The management committee is considering an expansion of the movie theatre. One group claims that an enlarged movie theatre would attract more patrons. The other group claims that enlargement of the theatre would not result in any increase in movie attendance. Which of those groups would you expect to support expansion, and which would you expect to be opposed? Do you see the problem?” (11/11/24)

https://www.econlib.org/the-problem-of-induced-demand/