You'll find these 4 different 'crates' at the casino. None of them require keys, but they do require money to use.
Each have their own separate monetary reward ranges, scaling up with their tier. Tiny Tantrum Machine is the cheapest and has the lowest monetary rewards and Mega Tantrum Machine is the most expensive and has the highest monetary rewards.
These are gambling machines which means you can win money but you can also lose money.