NakaNaka:
You are always of course entitled to your own opinion. You may well be right that alien civilizations are too far distant for us to detect any signals. Then again, we definitely won't find such a signal if we don't even look. However, you are absolutely incorrect regarding the validity of the project for the sake of science.
Already, the data gathered and analyzed by SETI members has helped to confirm a number of known and suspected astromical objects such as pulsars, quasars, and other radio-emitting phenomena.
Additionally, the project fosters both imagination and education regarding space and, perhaps more importantly, science itself. While there is argueably just as much validity to the study of cryptography, there is no room in either project for blind ignorance.