and helps liquidity and mistakes, it's easier to send 2 coins instead of doing some maths to see if you must send 0.0002 or 0.002 for example, how many errors have you seen with decimals in etherdelta for example?
That's true but if you have to send 100000 for a simple payment these errors can also occur. The best is a token price in the range of 1-100 USD.