The game is free. I can download and play without spending any money. The game uses the F2P model with micro transactions. The player decides how much they're willing to invest. The game site makes this very clear.
The advantage is one does not have to pay up front to decide whether or not they like the game. A try before you buy model. Non F2P multiplayer games require continuous monthly payments. Not so for tanks. There is no obligation to continue paying to keep playing.
Your decision does not make the game a waste of money for the game was free. You're just not willing to spend money to advance, to win or gain the other benefits. This is your personal decision.
So I disagree. WoT is not a waste of money. The game is worth that which you're willing to pay.
Acknowledgement Avatar: Elizabeth King - Eidolon - 1998/99