Flag Planting in Oakview Cemetry

This morning, in preparation for Memorial Day, the local scouts (of which my son is a member) went along to plant flags on veterans graves. It was a damp wet rainy morning - perfect cemetery weather.

I have a strange interest in cemeteries - I like looking as gravestone inscriptions. Now, something I've seen here in quite a few places are graves that are occupied by one half of a married couple, with the surviving member having his / her name inscribed, but no death date yet. Basically, they are committing to be buried beside their loved one when they move on. It doesn't bother me that they do that - but to me it jest seems a little preemptive - I know I am not going to live forever, but I'd rather not have my name on a headstone till they are pretty sure that my heart has well and truly stopped beating.

On that, I seen a couple of grave markers that raised questions See below-
Now, the good Mt Christopher M. Schryer passed away in 1933, aged 64. His wife, Agnes, seems to have felt committed enough at the time to get her name carved into a stone, and placed beside his. I guess there is a chance that they both decided to place their stones there before he died. In any event, she was 70 at the time of his death.
Her marker stone is shown above, but note how there is no year of death inscription! Therein lies the mystery? Does the body of Mrs. Schryer lie here, and nobody ever got around to carving the date? Maybe she had no living relatives. Or did Agnes, at the ripe age of 70, decide to remarry, and now lies at the side of someone else? Or is it possible that, somewhere in Royal Oak, Michigan there resides a fine 144-year old lady?