[DenisM]

Coin price is determined by (amount of $ chasing coins) / (number of those coins). Tether is effectively inflating the $$ side by pumping USDT into the system and making people believe USD and USDT are virtually the same. As long as the game continues the prices go up, which benefits everyone in the coin scene, hence everyone is playing along.

Also I imagine that major exchanges could get discounts on volume USDT purchases - this would allow them to paper over their own cash shortfalls in exchange for lending legitimacy to the scheme.