If I Retry, do I keep my star bits?

When you die, you have an option to either Retry or Quit. Quitting allows you to access the shop, where you can spend your star bits in the upgrade shop.

If I choose to Retry, rather than Quit, do I get to keep the star bits I earned on the run I just failed? Or do I just start over normally?

I'm mostly wondering because unless my star bit count is carried over, I don't see why I would ever want to Retry without spending what I have earned in the store.

Retrying is just a quick way of starting another game of the same game mode you just died in.

Your star bits are saved, but you might still want to quit and spend them first — so you have a better chance of survival on your next attempt.