For what it’s worth, I doubt they have plenty of life left in them for flashlights either. Look at the battery voltage discharge curve, and you will see that it is very flat, even under moderate load, until it is almost completely out of capacity, at which point the voltage plummets. What you likely observe, when you put it in a flashlight, is that the voltage has recovered enough, or it remains high enough, such that it will work brightly when you put them in. Don’t be surprised if you actually need your light, to find it going dim, and then off, in no time at all, when you really need it, if you choose that option.
From the graph, Discharge Profile Constant Current Discharge, you will see that they are still at 1.4V, under load, almost until the point of being totally empty.