And they shouldn't - because the Spanish looked like quality whereas the English did not. The Swiss were lucky, both for the goal and to keep 11 players on the pitch. They employed the kind of tactics teams of old used to use to try to neutralise Pele - i.e. keep kicking him. That said, Spain should have scored many times. But with the quality of the forward line they have, they will.
And I am not surprised the Spanish supporters were and are underplaying their chances - it is often considered bad luck in many Latin countries to be too confident.