W600i Data Transfer bypass/alternative..just read

i have cingular and i realized that whenever i put mp3 on my phone from my computer through a usb cable they charge me 1 cent a kilobyte. Which is ridiculous because its my mp3's and im being charged to put it on my phone? How do they know that im putting this data on my phone? and is there a way to bypass them finding out im putting stuff on my phone withought them charging me because thats HIGHWAY ROBBERY ripoffs.

Thanks