for the top of the bench I recommend a varnish finish of some kind. My next bench ill try BLO or Tung or the like, from Agent Orange.
But my current top finish? paraffin wax and nothing else. $2 finish from the grocery store that is chemical proof and durable as hell. Gap fills if needed, and soaks in. You can eat off it if you wanted to, after brushing off the gun powder.
Apply with a heat gun till the wood doesn't eat any more. Let dry, then scrape off the surface layer of wax to re-expose the wood. Done.