As Bogie said, however, in the UK, with the number of roundabouts that we traverse, the wear on the left front tyre can be somewhat higher than the right side. It depends on useage.
I used to live/drive in Milton Keynes, the mecca for all roundabouts. I used to get about a 2:1 ratio on my front tyres. So as Shangani said it is dependent on where and how its driven