How would you end up without antibodies? The virus just failed to replicate in your system and died out of its own accord? Or are we suggesting the people with no symptoms are still asymptomic carriers?
You will only get detectable antibodies if the virus activated the adaptive immune system. This could be the case if the infection was successfully and quickly controlled by the innate immune system.
It doesnt mean thee are no antibodies It means the antibody test doesnt test the right protein.