When a Pillager loses it's crossbow in multiplayer, or is spawned in without one (also multiplayer), he holds up his arm in a way that might be offensive to some people, instead of having his arms beside his body like in singleplayer.

If a pillager is spawned in without a crossbow or loses it in singleplayer, he keeps his arms beside his body, much as the player would. But if the same thing happens in Multiplayer, he holds up his arm in a certain "historical" way that might offend certain people.

(PS: The pillagers only keep their arms up when a player has been close to them, but they keep them up even without a player around them)