....sigh you are for real. People really need to be told what sarcasm is these days. My god, your god , all gods. /s
https://eu.battle.net/support/en/article/24258
using software to automate and all other things is not allowed. only game open in multi accounts is allowed. SO mulitboxxing normally is okay. But using bots or other software is not.
So they clearly state that multiboxxing can be done with software that is NOT allowed.
and no , most laws are mad because of either breaking the rules and hurting people, damaging stuff or creating situations that are not save. Or to stop abuse :S