Vehicle turning with zero steer in Vehicle dynamics blockset. Why?

Hello,

I feel vehicle is cornering even at zero steer.

For reference, I am using 'Increasing Steering Reference Application'. With very simple modifications shown below to keep zero steer, I see vehicle is turning, and showing non-zero beta and lateral forces on axle.

I haven't gotten the cause. I also tried logitudinal driver, but no luck. I tried Double lane change example also, but found the same problem there too.

Any help is much appreciated.