Thankfully for me I've been using white foam for all of my stones. So if there's any foam showing, it just kind of blends in with the rest of the stone. I haven't had any issues, but I'm totally keeping this in mind when picking up foam for my next round of tombstones. All my white foam was free from work, but I no longer work at the place so I'll probably have to actually start buying it.
For now, I do have two stones that were nicked during last season and need some touchup before going out this year. I consider an opportunity to rework some of the paint jobs on my stones since I'm still learning how to paint them so they look real-ish.