This is all my opinion.
They (snakes) do not know their owners, they know pattern of behavior. A owner will typically approach the animal in the same fashion every time the same way. Now someone new will most likely approach the animal with hesitance and fear, that I believe the animal picks up on and will be more likely to strike. This is why most horrible events you hear of happen when a handler is under the influence and not conducting themselves the way they usually would other wise. Or showing of for people, again not going about business as usual. As much as We'd love for our beloved pets to know us, I believe they simply do not.
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