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.

$100 per month seems reasonable for a crypto dev who‘s prototyping a new app. But make it easy to cancel and use “virtual cards” like privacy.com.

$10 per month for a student.

$10 per month for a student seems high, actually. There were months when I had to make do with tens of dollars for an entire month of groceries when I was a student in Chicago.