Many people find hope in exploration, discovery, and pushing physical frontiers. These were necessarily parts of human history that shaped our intuitions and desires and I think without new frontiers people get cynical or bored that can lead to some awful behaviors and outcomes. It's the same with scientific research it doesn't need to take the majority of the public funds but there is a minimum especially for some planetary scale science efforts.

We have so many problems to fix isn't a good reason not to explore and inspire, I'm sure there were ancient people who thought investing in roads was a waste of public funds why do we need to connect to other cities or lands if we have problems already, but some of those problems were resolved with trade or treaties or pluralistic cultures the roads allowed.