I did an exercise several years ago one weekend and it put things in perspective.
I asked myself a question... "If money was no limiter, what would I do?"
The answer was along the lines of do more cycling, spend time in the gym, cook better food, develop a circle of friends.
So then I thought, well what can I do right now whilst still working to improve these things too? Would I turn down a $9 lunch if it gave me the chance to spend an hour with friends company I really enjoy by going there? The trade off for $9 in that case was worth it. Another scenario, I needed a new bike for commuting to work and fitness. Would I get a real cheap, crappy one or would I spend a few hundred dollars more for a comfortable, reliable one that would last me years? I figured cycling is a huge part of my life and I get enjoyment out of it so I didn't mind spending more on it.
However, if money is an issue on things I get no enjoyment out of (e.g. buying fancy clothes) I ruthlessly cut out spending, because I get no happiness from buying $200 Nike shoes.