Weird. Is your wife's phone nearby by chance? The only time this happens to me it's because we are both walking to the car together and her phone unlocks it before mine does.
That sounds like some software guy somewhere didn't realize that those seats in the car aren't only for carrying air but that actual people or, gosh, occasional other drivers ride in them too.
Sadly this is rather symptomatic for many things coming out of Silicon Valley (not only Tesla).
I was sure you were going to complain about the windshield wipers "automatic" mode