What's the influence of noises when electromagnetic waves are used as a power source
RF noise doesn't affect power delivery - random noise can't cancel out the transmission power of the RF signal since the noise and the signal are uncorrelated. In fact, the power of the noise gets added to the power of the signal, although the noise power is very small compared to the signal and doesn't make a difference in reality. (There's many, many orders of magnitude between noise and signal. The hard part is getting enough power so the device can operate properly, not avoiding the noise.)

Also, most passively-powered RFID devices are coupled magnetically, effectively creating an air-core transformer between the RFID reader and card. It's very difficult to receive enough power via regular radio waves in order to power a microcontroller like in those cards.