A group of photographers went out to dinner... (Jokes)
As they sat at their table, taking photos of their food for social media, one of the photographers realized he hadn't been given water. He approached the bar and asked for a glassful, with which the bartender obliged.
Rather than immediately leaving, he stood there and stared at the bartender for a moment before returning to his seat. Soon enough, he found himself thirsty again, and took another trip to the bar, and once again stared at the bartender. This happened again and again throughout the night, with the bartender becoming progressively more frustrated by the photographers persistent requests for glasses of water and uncomfortable stares.
Finally, on the photographers twelfth trip, the bartender loses his cool and yells, "Take a pitcher, it'll last longer!"