I just bought my fat bike so I could get rid of my 27.5 hard tail and maybe 29er full suspension because they are heavy. The new/used 2019 Specialized Fatboy is much lighter. I plan on riding it everywhere on all surfaces, hard pack, gravel, sand, mud, water, whatever is in front of me. The first ride was in mud, one of the reasons I got it because the trails are muddy and standing water in the spring. I tried a few times to ride my 29er through it and made by sheer determination. This new bike handles it way better.
I would and plan on taking it on long rides. It rolls really well on gravel roads.
There are quite a few videos on YouTube of people bike packing on fat bikes, going really long distances some of them.