Generally, adult women don't like being called "girls" any more than men like being called "infants". It's insulting. Anyone who persists in using the term is going to find it extremely difficult to get a date with an actual adult. Adults generally don't date people who come across as being either extremely patronizing, or a closet pedophile.
It's true that the word "girl", and various other baby talk terms such as "tummy", "vacay", "fave", and "brekkie", are used a lot in Cosmopolitan and other magazines marketed exclusively to pre-adolescent females. It's also true that the N-word is used a lot in rap music. Devotees of both forms of media often use the derogatory terms to refer to each other, but it doesn't mean it's OK for outsiders to use the term.
You have the Constitutional right to try to pick up an African-American by affectionately using the N-word, or to continue trying to pick up adult women by using patronizing language. You're also within your rights to tie a 3-day-old dead fish around your neck every time you go to the club. But if you stay committed to a strategy that's guaranteed to present you in the worst possible light, please don't bitch to the rest of us about the fact your game isn't working.
There are a substantial number of adult women who don't mind being called "girls", however they tend to take an extremely childish approach to life. Mustachians, by contrast, take an adult approach to life. So the set of adult human females willing to tolerate being called "girl" contains few or no Mustachians. There's zero overlap. It's like looking for a mime at an auctioneer's convention.
If you're looking for a Mustachian woman, avoid women who tolerate being treated like children, or who express a desire for it. Start checking out women who insist on being treated like an adult. Expunge the word "girl" from your vocabulary and your online dating profiles, unless you are in fact talking about a pre-adolescent female. The word is a major turn-off to any woman who actually pays her own freight and wants to be treated like an adult. Your odds of finding some hot Mustachian action will be infinitely better than it is now. (Right now, sir, I fear your odds are zero.)
Now, in the specific case described by the OP, the female person who's pretending she was cosmically forced to buy the SUV is in fact a "girl", that is to say less than an adult. Adults take responsibility for their own decisions and run their own lives. She refuses to do that, so by definition she's less than an adult. I'm actually OK calling HER a "girl", provided we refer to a man of a similar age, in a similar situation, as a "boy". I propose that we start doing exactly that.