When to use your pugio

[Quintilianus]

Crispus, your mention of the expenditure frequently lavished on pugiones, and the fact that they seem to have gone everywhere with the soldier... It's a good place to invest your wealth, perhaps the piece of kit least likely to get stolen, easier to keep track of than coins, plus a stylish accessory and defensive armament to boot.

Yeah, but the Roman legionary could deposit his money in an army banking system, so was there any need to invest it in an elaborate pugio unless he liked the look of it and wanted to show off?
And of course it was possible to lose it or be stolen, why else are there so much engraved names found on equipment for no other reason then to express ownership?