The Problem With a New Bike

I would love a new tarmac. It's been six years. You're so overdue for any bike. And the carbon will like last for it's just so hard to rationalize replacing that bike when it works. The problem with sand and beaches is that they're often pretty cambered. So my question is, do some of my runs in the sand, not soft sand because I'm not that fit? Am I better off on the boardwalk than the pavement?