Technically yes - by becoming a liquidity provider (LP) which earns APY.
Why does RUNE need to be the settlement asset in every pool?
If each pool is comprised of two assets eg. BTC:ETH then there will be a scaling problem with n*(n-1)/2 possible connections. By having RUNE one side of each pool, $RUNE becomes a settlement currency allowing swaps between any two other assets.
Additionally, having $RUNE in a pool ensures that the network can become aware of the value of assets it is securing.
What is the monetary policy?
The goal is to have a fixed supply at all times. Instead of constantly emitting (infinite supply like Cosmos or Ethereum) or reducing the emission down to zero (Bitcoin) the team elect to match emissions to the difference between current circulating supply and the max supply, as well as burning fees. This means there is 500 million progressively emitted to nodes for security and liquidity over time.
Why can’t I upgrade my BNB.RUNE or ETH.RUNE to THOR.RUNE.
You will need additional BNB or ETH in your wallet to cover the tx fees to upgrade.