Say again s l o w l y:
Bars are awarded, not just bought and worn.
Awarded? Well, maybe by an employer. Look at it this way: in some jobs or training organisations, you have to wear a uniform. Nothing wrong with that. Commercial pilots, soldiers, traffic wardens, air hostesses...
If you are a private pilot you don't have to, and they have no significance. You can wear 38 bars if you like. Personally, I find a nurses uniform rather fetching.