I'd say it's because they are human.
Is there anyone who has grown up without much who has not seen this? It's much more common than rebadging your Tesla. I was told by a relative that it makes the liquor taste better. It's a variation of the placebo effect, I guess. Don't knock it until you try it.
I would certainly be embarrassed like you. In fact, before I bought my Tesla l looked at expensive, flashy vehicles as embarrassing and showing feelings of inadequacy even without the rebadging. It does make you wonder about the kind of person that could have a 60, rebadge it a P100D, and not give a damn when he takes it to the service center, or when supercharging. I'd be embarrassed as hell but I kind of envy the fact that he couldn't care less. Maybe that's a virtue rather than a serious inadequacy? I think the answer depends on the particular person.
Looking at it as sad might be like looking at the glass as half empty rather than half full. I'd like to get the know the person first, if I met him at a supercharger, with his 60 badged out to a P100D, and then decide. The people I know who I could see doing this are much more interesting than the ones who would not (like me).
