I think the reasons why people are inclined to criticise lavishing money on what many see as pointless projects is at least two-fold.

1) Many people are unaware of the underlying research and its possible benefits and see things like space programs as Governments indulging in expensive showing off. Possibly, more transparency and better public education would help.

2) It is tempting to look at a situation in which billions of dollars are spent on firing another piece of hardware into space, while millions of people are starving and living (and dying) in squalid conditions, and wonder about its morality. The fact that these people are suffering because of personal and corporate avarice, rather than because of scientific expenditure, is easily overlooked.

There never was nothing.