IMHO the number of transactions has nothing to do with the price. In fact the higher the price, the higher the fees per transaction. At least in relation to the amount of value transmitted in comparison to USD. 1000$ per BTC and the fee is 0.0001 * 1000 = 10 cent. 200$ per BTC and the fee is 0.0001 * 200 = 2 cent.
Whoever said it did?
Most traders don't care about the absolute price. All they care about is volatility and the % movement in their trading window (for many the trading window is minutes or hours).