I agree that the charge is getting high - possibly because Roam isn't competing anymore. I think the original $5 was aimed squarely at weaning us off of Roam. It does add up for more than one phone.
One tip for this. We travel with a LOT of devices, cell phones, tablets, laptops, so we do the following.
We designate only one device to be the roaming device and all other devices have roaming turned off. If someone gets lost in the parks then they have permission to turn on the phone for the day to get in contact. Set the one roaming phone (usually mine as I have tend to get occasional work related calls) to be the hotspot for any other devices in your family. As long as they are close to you they will have reliable wi-fi on their phone too, not relying on Disney's spotty coverage. Now we have 6 devices on our Rogers share everything account, so we have a TON of data (even at a lower tier) so don't really worry about overages. This does tend to drain the battery on the hotspot device fairly quickly, so I also carry a battery bank in my sling bag with about the same capacity as my cell phone's battery, effectively doubling the life span.