Q: What good to find Special Weapons in Story?

I have a question about finding those Special-Hidden Weapons in Story, (Loathsome Thing, Blaze of Glory, etc…)
What good are they to find?

Other than the obvious, to use a ‘better’ gun during Story,
but is that it?

I already ran through the Story on Normal, and will again on Hard/Legendary/etc…
but is there any real reason to search for these?

I thought it might unlock the skin/weapon for use during Warzone and such,
nope, that doesnt seem to work (nor does it cause the pack rng to drop these cards)

So, I’m just confused as to why I would spend time to find these,
when they seem to be a one-and-done thing for Story

I found Recluse just the other day… and was less then impressed by it honestly. Outside a semi okay reskin of a covi Plasma Launcher, it didn’t do anything special or grant an achievement of some sort.