I fully intend to log into someones league account to buy myself skins
Why are you going to log into someone else's account to buy yourself skins?
I can't afford to buy myself skins and someone else can
You are stealing by logging into another person's account to buy skins for yourself. This behavior is illegal and could result in you being arrested.
Don't try to tell me what to do. I will jack their account if I feel like it.
Taking money out of someone else's account is a breach of loyalty, a theft and it's just a way to use other people to benefit yourself. Stay out of other people's league accounts and earn your own money for skins.