It IS a licensing issue. In the cutthroat pricing environment of MPEG-2 receivers, most manufacturers cannot justify even five or ten dollars more on components
to add an AC-3 circuit. Since there are already stereo receivers on the market
that can be purchased off the shelf, which accomplish the processing of Dolby Digital, it was an easy solution for the FTA receiver makers to add a jack that
passes the necessary digital stream to such a device. It avoids the expense
of both needing a Dolby license or having to pay for a hardware solution.
to add an AC-3 circuit. Since there are already stereo receivers on the market
that can be purchased off the shelf, which accomplish the processing of Dolby Digital, it was an easy solution for the FTA receiver makers to add a jack that
passes the necessary digital stream to such a device. It avoids the expense
of both needing a Dolby license or having to pay for a hardware solution.