This feels like a response to poor user engagement and given that on-going purchases are a big part of Amazon's aim for these devices that would be a problem for them.
Remember too that this could / should be a one off cost to Amazon for each Fire user. When / if your parents like the tablet and upgrade in the future, you'd hope that they then had enough familiarity not to need it again.
I agree that it's a response to poor engagement, but if that's the case, I think they're trying to solve a usability problem by throwing people at it. Apple's biggest selling point for the last 4 years was "It doesn't come with a manual because it's so simple". Amazon seems to have given up on simple, and on manuals - their equivalent phrase would be "it's so complex that we've hired people to help you use it, 24/7".
I think that although this service is a small step forward for currently confused users, it's likely a huge leap backwards, because it'll leave those people confused forever, and dependent on the "amazon lady" to use their tablet for them. On the surface, this seems too ridiculously obvious, so I have to imagine that they've got an awesome game plan that is yet to be revealed.
Thinking about it with that in mind, this could be Amazon using Mayday as a way of learning where people have pain so they can remove it in future versions.
Perhaps it should be seen as the largest usability study in history?