I will add that in the novel Cale's uniforms are shoddy and the embroidered star symbol is a massive mess so it's a little easier to tell them apart. But yeah as everyone else said, it's mostly to piss them off and also hide their own identities so they can't retaliate against their families and friends.
I think here wasn't said, a slight spoiler warning too, at the start as the team was only choi han, the uniform was made by cale himself, at least the symbol, that's why it was crooked and so on, cale wasn't aiming for a replica either way. This served as more mocking lol, afterwards, when the team gets bigger, the uniform get prettier and nicely done
Can someone tell me why cale is making his grp wear the organization clothes? They are fighting the organization right? So why would they need to wear them? Wouldn't it make the elves confused who the enemy is?