Trust isn't binary & is necessary for humans to co-operate. 

You trust people to adhere to driving protocols every time that you get in your car.

How you mitigate the risks that come with trusting individuals is a personal decision.

I'd rather place a small amount of trust in the individuals I do business with than a large amount of trust in a govt or institution. 

WoT is about increasing the cost of breaching trust rather than eliminating the breaches completely. Trust should be in the provider of the value rather than in the consumer or the money.