1. I'm not talking about botnets, I'm talking about sites that crawl your content to copy your database and mine competitive intelligence on it.

2. Clients should be running firewalls anyway, yeah, yeah. 99% of the security holes online are because of "shoulds". In the wild many, many, many people will assume their IP is unguessable and then it will leak _somehow_. A single hacked device on the other side of the firewall, or a misconfigured firewall, etc.

3. Well that might be true for your home internet, but it's almost certainly not true for your mobile phone unless you live somewhere weird.