As suggested above it's a sensitive issue as you can imagine it being used in cost of living comparisons, and so on.
We just get 10 or so '1st local' postage lables, and keep them on hand. Beats having books of denominated stamps and having to buy additional, 1, 2, 3c stamps when they hike the rates (as seemed to perpetually happen in the US, and also in the UK, which introduced '1st' and '2nd' stamps quite some years ago now...).
I think the point is those lables don't indicate a value. They arguably look a bit like some random kiddy-stickers. So in place of that, they give
some idea what they actually are. Perhaps if they were marked 'Postage stamp' it would be more literal... but then someone could ask 'But what kind of stamp, and what value... ?' ...
I can understand the question (you're an engineer right?

), but can you think of a better solution?