Antes de entrar, dejen salir

Question

"Antes de entrar, dejen salir" is a sign you will sometimes see on public modes of transportation: "Before getting in/on, let people get out/off". - Cordobesa

I would like to thank cordobesa for telling me the meaning of this phrase, and I found three related pictures online. But I have a question about the third photo. Since the poster is issued by Ministerio De Trabajo E Inmigración, not by Metro, I wonder if there is any other meaning by that.

Photo 1

Photo 2

Photo 3

Answer 1

The meaning is the same.

Spain has a big problem with illegal immigrants, so this is a joke.

Thank you very much, Annie. But does it imply "If you want to immigrate, someone else has to emmigrate first"? Or, "If you want to get the job, someone else has to quit first"? - joygogo, Dec 30, 2013