It could also be used for the NPCs in your group that have died once they are in. Like buriyng them in the backyard of the safehouse. Just like they do in The Walking Dead. That would be awesome!
I don't really like the idear. It's nok like it's the first thing i'll focus on in a zombie survival. I won't even think about it. Why should you make a bomb other than kill yourself?
I love the idear, but I isen't it hard to implement. Having a horde trying to do the eating animation, may kill the FPS? I dunno, but I love the idear!