It's not 2005 any more, Sun Microsystems is long gone. You won't raise any money from a business model that gives away your best work or selling support contracts alone.
Caddy is a real innovation, and brings web server defaults bang up to date - it makes loads of complex configuration easy. It's already distributed in the finest tradition of free software - a liberal source code license with no restrictions. You can do what you want with it.
Like GNU in the 80s and OpenBSD in the 90s, Matt is selling the most convenient package and yeah - if that's the one you used and relied on for your infrastructure, you've got to pay, and not very much.
Matt has clearly worked hard at making that payment support as much as possible in terms of convenient corporate deployment. I really hope that works out well, and am glad it's a business model that supports Free software without any compromises.