A Lowball 1905 French 50 Centimes

Over the past few decades I have collected a complete date set of the silver French 50-centime coins issued from 1898 to 1920. Most of the earlier dates are in VG to VF condition and the later dates from XF to AU, not counting a couple of UNC ones I bought. Apart from the UNC coins, almost all of them were from junk bins in France and England, mostly costing just the bullion value or less. This coin really stands out on my album page:

I cannot understand how it got so worn. Apart from a few scratches on the reverse, which look fairly new (maybe from contact with other coins in the junk bin), the wear looks even and old. These coins were demonetised in 1928, but had effectively disappeared from circulation by 1921, when they were replaced by the Chamber of Commerce 'Bon Pour' coins. And from my perusal of French books and coin magazines, plus talking to elderly French people when in my teens, I got the impression that they more or less vanished during World War I, so a coin minted in 1905 might only have circulated for 10-12 years. I quite often find holed and otherwise mutilated examples of these coins, usually in British junk trays - probably brought back by WW1 soldiers as souvenirs or love tokens or simply to show how they passed a few boring days in the trenches - but I've never seen another as worn as this!