We've removed the Caddy-Sponsors header
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I have no objection to Caddy monetizing, and I hope they are successful, but don't penalize small users to get there.
In my day job, I work for a large company and we pay for OSS software all the time (RHEL, Nginx Plus, lots more), and if Caddy starts to get popular, I know we'll have no issue paying $10,000 a year or more.
Go after large enterprise, and keep it free for hobbyists. Small/Medium businesses are painful to deal with, and you might as well let them use this for free.