MustardAndOnions
Winger
I think it's more likely it's because Smith has already played for England, they know his character, how he gets on with the squad etc. I don't think it's a slur on Robinson, Smith was just the cab off the rank, Robinson could likely be #2 and on current form might be knocking on the door as a batsman alone.
Robinson kept wicket on the lions tour in India mind this year