The reason that you cannot break chests in the first 20 seconds is simple. If you break the chest you will get all the loot in one go. If you have to take everything separately, your team will also have the option to grab something.
I know, late response.
But no, this is not already in the server. Every time you join a game joint you have to vote for chests or HP again. In some games, these kits are automatic, but not all of them.