At one time it was understood that someone had just left this life and, even if you don’t believe in an afterlife, respect for the dead and their family’s loss was enough to cause people to allow a funeral procession to pass unrestricted.
You don’t seem to understand the seriousness of death and the weight that it carries to a family. Maybe you’re young or maybe you just don’t get it yet, but you will eventually. It’s not a point of honoring someone’s achievements, but respecting the fact that someone’s life has ended and their time on Earth is over.
How you make the leap from my comments to the idea that I don’t believe in an afterlife is just amazing.