I think a lot of places do this for convenience, and don't realize the risk it puts them under (not that you are unaware of this, just that others may not be).

I think a lot of places do this for convenience, and don't realize the risk it puts them under (not that you are unaware of this, just that others may not be). Whether they have everything generate its own wildcard certificate, or create one wildcard and share it to everything, they've created a significant security risk. Namely, any time a wildcard cert and private key leaks, the attacker can now impersonate literally everything behind that name. By using wildcards everywhere, they're creating tons of leakage points, and only one of them has to leak the private key and the attacker wins, particularly if they can grab it without the user being aware.