Fair point and I agree that it could be confusing that they appear in the Channel Lists screen but the fact remains that the EPG are driven from the EPG data and, because there is no data for those channels they do not appear. Basically, a query is made on the EPG data along the lines of "Give me the EPG data for the selected channel list for the selected day/timeframe", and the data that is returned is displayed. No data is returned from this process for channels with no EPG data which is why they are not displayed.
Yes, technically it would be possible to return empty rows of data for the channels which do not exist in the Freesat EPG but it would require some significant work as the same EPG search mechanism is used throughout the Web Interface and it is likely that having empty rows of data returned from EPG searches would break other functionality in the Web interface.
Despite several more cups of coffee since my earlier post, and my brain now working hopefully at full speed, I still can't fathom what earthly use it would be to have an empty row of data on the EPG screens for non-Freesat channels. Can you enlightlen me please?