Why is host able to start the game before EVERYONE press ready?

I mean, ok I understand the need to solve the problem with afk players that delay the beginning of games, but when we enter a game we need to check at least players levels and win conditions. I ve been in many games that hosts just clicked off all wining conditions and we ended up trying to find the last villager of an enemy hiding in a gigantic map, just because the host deliberately started the game before anyone notices that. In other cases the host started a game before I decide that I wanted to play with lvl 10 allies against his team of lvl 25.
At least devs should offer players (and not only host) a button to stop countdown if someone is not yet ready to participate in a game. If devs feel that this can cause a delay in having a game started then they already have the option for the host to kick the player who is afk for more than the necessary ~10 secs that someone needs to check levels and win conditions.
I would prefer being kicked out of the game lobby by a host who deliberately wants to trick me in a game tailored on his team than having to resign at first min and ruin the game for all.
What are your thoughts?