So, the title of this thread is "Mustachian People Problems (just for fun)", so I'll share a story.
Years back, my wife and I were trying to understand where we were spending our money so we -- oh, heck, you know why!
I asked my wife how much she was spending on gasoline to go to work each month so I could put that into our spreadsheet.
What she didn't know is that whenever I had to run a quick errand to the store I would often use her car and fill it up with gas as an "I love you". I had been doing this for years.
So she couldn't actually remember the last time she had gotten gasoline for her car. I kept asking her for several months before I fessed up.