Assume it was 1-click and 100% automated to deploy, run and update a Hub.

How much per month would you be willing to pay to run one? 

No direct economic incentive other than you know you're supporting Farcaster decentralization and you have your own copy of the network.

OK, if you're answer is you wouldn't run one.

Working on Farcaster and Warpcast. Longer thoughts at https://dwr.email

As a consumer, I wouldn’t pay. 

If I was building on it, I would consider it. Up to $30/mo, which is the most I typically pay for any side project.