Banker splashing occurs when players are attempting to sell their chips back to the banker. Often, at the end of the game, sometimes at 3:30 AM, players are hasty and just toss their chips at the banker. Chips belonging to different players will get mixed and trouble starts.
Tossing your chips at the banker is like tossing your money at the host. It is rude. Before presenting your chips to the banker, count your chips and place them in a chip rack for a fast exchange.