Shame usually doesn't work in the US because speed limits are routinely underposted, usually by design. So e.g. 10 MPH over is not only socially acceptable, but

Shame usually doesn't work in the US because speed limits are routinely underposted, usually by design. So e.g. 10 MPH over is not only socially acceptable, but often expected. However they will usually keep drivers under 10 over the limit (that it believed by many to be the threshold for an officer to pull you over).