Why are most people willing to spend so much on caskets, especially when they then can't afford a headstone?

My father ped away a year ago, and my mother was talked into an expensive casket by a slick funeral home director despite my protests. Being a very frugal man all his life, my dad would have turned over in his grave if he'd been put into it yet! He never in all his seventy-five years spent as much on a car as my mom spent on that casket, and she did so even though we could scarcely afford it. I know it was due to nothing more than tradition, peer pressure, and not wanting to feel guilt. The thing about it that bothered me the most was when I realized at the wake and funeral that no one could even see that casket, it being dd with a flag! At any rate, what's done is done, but now we have no money for a nice headstone. My dad was really active and loved in the community, and was many times over for his contributions and work with youth. I feel he deserves better that the basic cemetery marker that now lies at his gravesite. Why are families willing to pay so much for something that's being immediately put into the ground, holding just an empty shell of a body? I have never understood this, especially since most people, when asked while they're alive, say they wouldn't want such a thing?