Ahh, now I think I know what's going on.
The fields are not being primed per se. What happens is that Crome tries to be clever as soon as it sees a field that may be an address, a phone number or a website and suggest some values based on prior data being entered. I've seen that myself, and only if the user hits Enter the fields are actually filled with the suggested values.
I haven't investigated further, but there may be a way to turn this "feature" off, who knows.
Peter