The only place that I've seen open networks to be common is in beach rental communities. Basically these are areas along the coast with tons of homes that are rented out on a weekly basis for vacation rentals and many of those homes do have open wireless networks. If I owned a vacation rental house I'd actually do it as a wired only service. Go ahead and bring your laptop, but you're going to have to hook it up wired to the connection. That way the guest can use it, but it's not out there for everyone. We've rented homes that had both and it make any difference to use which the house has as long as it has internet service of some sort.