[bojan]

Well, you can't look at all that through the prism of "benefit" or, let me be blunt here - money.

Science and knowledge is not about money and not about immediate benefit (business). There are countless examples of "useless" knowledge
that suddenly became very useful..

In case of knowledge about existence of exoplanets and whether they support life (intelligent life, even), the immediate benefits will be mainly philosophical, but I am sure there will be also significant impact on our everyday life - because this knowledge may change the way we think about everyday things (religion, for example - this aspect of human activity is pretty useless from practical-business point of view (regardless of which side of it we are) but it influences our lives very much, whether we want to admit it or not..