Is a single pak the only way to package a game?

I’m quite curious on this because many Unreal Engine 4 titles seem to present a massive problem. When patching them I see a lot of developers having to basically make a second copy of the game on a hard drive and then patch the game basically meaning that people are having to make sure the game x 2 available of space is there. Is there a way to split it so it isn’t one massive file and if so how exactly? I’m not quite sure where this goes exactly so tossed it here.