Far from a silly question.
Kia quietly abandoned the radio TPEG data services about 2 updates ago and all data now has to come from the LIVE (TomTom servers) so you have to have Hot Sport / Internet connectivity. This was probably when they introduced Kia Connect for new cars and did not want to continue paying for the TPEG data feeds.
It's a bit of a cheat as one of the selling points (for me) was the traffic updates direct to the Nav unit when you did not have a Hot Spot set up. But there is little we can do. It looks like the Nav unit still attaches to the TPEG service but obviously is not receiving/decoding congestion data - I'm prepared to be proved wrong of course.
Edit: I should have said the above applies to the UK. It's quite possible that the Nav unit does receive local traffic data, via the radio TPEg service, in other European countries. It's also possible that other countries DAB services transmit the DAB equivalent of TPEG - something the UK broadcasters did not adopt and the government did not support because (at the time) "the take up of DAB receivers in cars does not justify the investment" Rant over!
