Theres no " main" economic nodes to point at. This is why we say you must run your node to broadcast your txs. There are certainly nodes that can have more TXs broadcast through them but you must pay the fee everytime you do so.

So lets say for arguments sake certain bad actors with alot of bitcoin wish to try to influence a fork one or or the other.

As they " spend" their coins with fees the stacks they have will inevitably diminish as most of them would want to simultaneously coordinate expenditures to influence which way the miners lean. This would in turn drive up fees higher each block therefore eroding the malicious actors stacks of bitcoin as they spent them with only the intention of influencing the fork instead of actual economic activity.