You'd lose bandwidth and gain liability. Not a winning proposition.
There are only downsides for me, but I think they are limited: - My router lets me set the bandwidth limits for the guest network. I set it to 10Mbps down/1Mbps up which is unnoticeable. - My ISP has no data caps. - The laws here are not draconian
It looks like this concept is super old: https://www.schneier.com/blog/archives/2008/01/my_open_wirel...
If you were a crook, would you use a random open wifi for your illegal stuff? Wouldn't you use Tor or some proxy on top of that?
Most of their defense is based on the assumption that you have all the same protections as a network operator. However, as the article points out, this has never been tested in court. So you might be fine, and you might go to jail, we don't know.
And even if you do get network operator status, there are still legal notices and copyright systems you have to comply with.
And thats all just copyright. That article doesn't deal with more serious online crimes.
If the FBI finds someone downloading child porn from your network, you will be arrested. You will have to convince the police that it was someone else. Even if you don't end up with any serious penalties, that's a hell of a lot more hassle than I'm willing to put up with.