Well old sport, there are just so many factors that must be taken into consideration! Given whatever environment you're in, are you going to find the time to decapitate a zombie and, keeping viruses and pathogens and the like at bay, remove the flesh to create a memento? Then you have to account for space. If you're traveling constantly, a ton of skulls is an extremely unnecessary encumberance. Also, once everything is said and done, there aren't going to be any visible signs that this was a zombie skull. You might as well be a serial killer that keeps his victims' skulls at this point, because close friends and family that stop by to visit won't be able to tell the difference. I think pictures, journal accounts, and items taken off felled zombies are far more appropriate and convenient.
One of the characters in my book Conquest of the Dead has a collection of skulls across the front of the roof rack of her truck, each with a bullet hole in it's head, but then she is a psycho killer anyway.
Personally I'd stick with marker pen crosses on the car door , they don't smell so much
I plan on having to kill too many Zeds to keep count. And that's just to survive. It doesn't take in to account going out and clearing a part of town with a larger group. Keeping trophies of people who are for all concerns victims themselves doesn't sit high with me either.
No trophies for me like a bodiepart. I think that I will strip them from there jewels, watches, necklaces, stuff like that. They don't need it anymore. That would be my trophie. I think I'll end up like B.A. Baracus after a while :P
I would collect some useful and unique stuff cuz (for info) in my native culture and customs, women or girls are forbidden to take the heads or skulls of their decapitated victim back home - only men does. In fact, the tribal rules were also flexible so women /girls of natives Borneo allowed to take parts in a war tribe but not on the hunting party expeditions which usually took several months in the process far away from home. So that's it people, ya'll hear it from me first ...