Yes, a lot of hotels do require you to sign in every 24 hours, at least that has been the case when we've been in Niagra Falls and when I was in California last year.Lots of hotels here in Canada do offer free WiFi which is great. It seems that the more "touristy" destinations (sorry I don't think touristy is a word) charge for internet because they can.
As for the Iphone info, that's exactly what I was told up here in Canada too so I am going to set my phone to airplane mode. I am renting a timeshare and paying for WiFi by buying a weekly card. I already reserved a cell phone for while I'm there but now am not sure if I need it as it's possible to use the internet through my phone to make free calls. However, that's outgoing. Unless the person calling me has one of the apps I have like Skype, then I will be charged roaming charges for accepting their calls right? For example, if I have a babysitter for my DD and she calls me locally on her cell phone and I answer, I'm charged. However, if my mom calls me via Skype and I answer via Skype, I'm not. Therefore, I think I will stick with using my phone and laptop for internet and outgoing calls (keeping my phone on airplane mode) and use the rental phone for all local calls. Is this a good plan?