I know relationships are larger than small moments shared at gas stations. I had thousands of tiny, beautiful moments in and around gas stations, still divorced.
Life is a fluid, evolving thing. Who you will be ten years from now is not who you are now, but it's also not something you have to deal with at the moment.
One day, that couple may throw dinner plates at each other. Would that improve his perspective?
So, enjoy it while it's there. Good for them. Those little moments are what life is about, if fleeting, but that just makes them all the sweeter.