“Adobe writes entries to /etc/hosts redirecting fake domains to localhost so it can probe whether the install is genuine.”
The hosts file is a piece of system infrastructure that root-level installers should not touch unless absolutely necessary. Adobe touches it to run a clumsy DRM check that any tampering tool can defeat in five minutes. The check accomplishes nothing. The damage to user trust and DNS hygiene is permanent. This is what software written by accountants looks like.