The summary was quite lacking. For those not wanting to rtfa, here's what it says under why broadcasting the blockchain in a way that can be picked up by low cast receivers is or might be useful. An AC post below also mentions that TV coverage may be better than mobile internet coverage.
This scheme makes it easy to construct affordable receivers that do not need mobile data connections in order to follow bitcoin traffic and to react to the received bitcoin payments. This would make it possible to build bitcoin counterpart for cash payment terminals, anything from a cash register to a coin operated self-service laundry. If the receiver application follows only transactions relevant to itself, it will be possible to build it using even an ARM microcontroller.
Also, it allows an alternative way to access the bitcoin network in cases where only a very low speed Internet connection is available. And, for all the tin foil hat wearers out there, this is a way to connect to bitcoin network without a trace! You only need online access when you want to make transactions yourself.
The data stream can contain other information, such as exchange rates between bitcoins and traditional currencies.