I think suggestions that you should pity him, assume he's poor, etc. kind of miss the point.
You know nothing about him. You don't know that he's poor. You don't know that he isn't. Reframing may make your thoughts a bit more attractive. But more to the point is, why do you care at all? So what if he's an epic douche who has 6 figure credit card debt? So what if she's a glorified prostitute who sells herself to the highest bidder? And so what if he's a kid making some extra money by transporting cars across the country during his college break and he wants to sit where he can see his assignment? And so what if maybe the car is actually hers and she's a brilliant scientist as well as a generous philanthropist, who owns the car primarily to be used for Make-A-Wish wishes for terminally ill people who just want to spend a day driving their dream car?
To me, the real question you need to ask yourself is not "what other explanations might there be for what I see?", but "Why do I care?" Are you so insecure with your own choices that you have to default to shitting on others to stay ahead of that insecurity? Do you feel deprived by your mustachian choices, with your sense of deprivation manifesting itself in jealousy and then pettiness toward someone making choices you wish you could make? Do you worry that others judge your older car and therefore react defensively when you see a choice at the other end of the spectrum?
Focus on why you care so much about the choices of other people--choices that have basically no effect on you-- and what that shows you you need to work on in yourself. That you care at all--good or bad--probably means you have work to do on yourself. Even if you see a guy driving a beater or a bike and judge him in a good way--"He's probably very responsible and sensible, with a good head on his shoulders and a nice 'stache"-- you could be wrong. He could also be a guy who just robbed a bank, shooting two people in the process, and wanted a low-key getaway car. But the real issue is why you care about someone else's decisions, and what need that fills in you, and what better ways you can find to fill or eliminate that need.
My least favorite thing about MMM and these boards is the sanctimony and judgement for those who make different choices. Someone wants to own a Porsche? Cool. I hope he gets out of if whatever he's looking for. And as long as he's making an informed decision and has done the cost benefit analysis and chosen what looks best, even if he actually asks me, I am going to say, "good for you for buying that car of your dreams, which clearly makes you happy". Because I don't care if his choices and values and finances are different than mind. His Porsche isn't, IMO, a morally lesser (or greater) decision than my 2000 Toyota Echo. It isn't until he starts complaining that he's broke or otherwise demonstrating that his choices are in conflict with his values, that it becomes anything more than value neutral. And more to the point, it is none of my business and has nothing to do with me.
