Refers to a way of playing Minecraft that is completely vanilla with no modifications. This means no plugins on servers, no spigot, and no client side mods for players (hack clients, optifine, etc.)
He uses a hack client, he is not playing on vanilla minecraft
When Bamboo is sometimes just too hard to clear
Man my entire garden is filled with Bamboo, this isn't what I came to understand of a "Vanilla Minecraft Experience."