There are 2 reasons:
1. PS3 had an wireless internet rounter: and with most PS3 in an bedroom or lounge room you aren't going to run an ethernet cord thoughout your house or upstairs for your 360 or give in to paying 100 dollars for that wireless attachment. An with many ISP providers providing all there rounters with wireless abilities its more convinent just to hock up your ps3 over wifi than the hassel with the early models of the 360.
2. Xbox Live costs money: Why bother connecting online if you aren't going to pay the subscription fee. PS3 owners might as well create an account because its quick, simple and its free to do so.
Of Course That's Just My Opinion, I Could Be Wrong







