The short version (after some Googling) is that some cars have one with certain tyres and some cars don't (mine included). It seems that you should have a tyre repair kit if you have normal tyres but won't have a kit if you have Bridgestone Enliten tyres with B-Seal technology.
Enliten
Bridgestone’s innovative lightweight tyre for reduced CO2 emissions and improved fuel efficiency. Enliten demonstrates a rolling resistance that is on average 20 percent better than a standard premium summer touring original fitment, and a reduction in weight that is 10 percent better, without performance trade off.
B-Seal
Part of Bridgestone’s puncture solutions portfolio, B-Seal is Bridgestone’s automatic sealant technology that guarantees air retention when nails, stones or other objects are embedded at up to 5mm in diameter in the tyre tread.
Might be worth a look as some people in some forums don't have a kit with normal tyres.
(Image from https://www.e-tronforum.com/threads/tyr ... r-kit.3207)
