A player of a Micropayment based game that gets all of the good items by paying for them instead of earning them through playing the game.
Player 1: "Wow, where did you get this cool sword and armor? You are only level 2"
Player 2: "I bought them with real life money, I don't have time to level up so I am a wallet warrior"
A player in a mmo game who spends piles of money to get all of the best items and equipment. Usually still sucks at the game.
*Premium tank firing randomly kills ally at the start of the game*
Ally: "You stupid fucking wallet warrior!"
A person who suggests buying something new instead of fixing an otherwise perfect item.
You: My <slightly old cellphone> is unable to check email. It says "Can't connect" using Wifi or 3g, or whatever, but other accounts I have work just fine, and altogether it works like a charm.
Wallet Warrior: You should buy a new phone at <big fancy mart-shop>.