Bugger. I was really excited for Let's Encrypt specifically for the possibility of a free wildcard cert.

I was thinking of building an app which would be under two domains like heroku.com/herokuapps.com and github.com/github.io and I rather not spend hundreds of dollars on two wildcard certs. Guess I'll just buy one and not use subdomains on the main site.

You mean I can issue multiple certs at each subdomain separately instead of one wildcard cert? That's promising. It's also OK on my personal use.

My initial reaction would be that is just stupid, but is there a good reason for that refusual? It is usually as a way to make money, but in this case?