Why you do this to me , HiRez?

So I decided that I go on my little brothers account and play a match to get him some worshippers/favors/xp . I played an Arena and I pretty much had these guys in my team

After I saw their decent 0/6 in min 5 I politely asked them to play safe and don't go aggresive. Their responses were like "Grow up " "It's only a game" "Don't act like a 10-years old"...I never understand the people that feed , are asked to play safe and then they keep telling you it's a game. Well yeah , IT IS a game but that doesn't mean I want to lose every game I play , right?