Everyone has a job to do. For astrophysicists and aerospace engineers, their job is space exploration. For those who participate in or operate charities, non-profits or even certain government programs, it is their job to fight hunger.
Meanwhile, we can't stop scientific advancement, exploration and the pursuit of knowledge that is for the benefit of all of mankind for generations to come. If you want to attack wasted millions, then attack the way celebrities and athletes are paid millions for their activities which contribute far less to society's advancement than what scientists and engineers do.
The amount of money spent to send New Horizons to Pluto is a drop in the bucket compared to other expenses of government. Really, you could plop anything in that statement "Why spend millions on war while...", "Why spend millions on campaigns while...", or "Why spend millions on corporate tax breaks while...".
The reality is that there is more going on than just world hunger. Maybe if we put out minds to it, as a united front, we could solve the problem. But one country can only multi-task so much. And, as far as frivolous spending goes, space exploration is the least of our concerns.
Dremer you are very much on point... the money spent on campaigns in some countries are total outrageous... the money spent by my own country Nigeria is even more than enough to buy 5 F22 fight jets to deal a heavy blow on those senseless boko haram that is trouble the nation.