Our 'Road Traffic Licensing Regulations’
(Straßenverkehrszulassungsordnung) stipulate a permanently installed lighting system. An exception is made for sports equipment, i.e. bicycles weighing less than 10 kg (it could also be 12 kg, I'm not entirely sure), which may be fitted with clip-on lights.
Of course, it depends on how strictly the local police enforce this, but manufacturers, especially back in the 80s, naturally had a better chance of selling bikes if they were roadworthy. Germans like as much equipment as possible, regardless of whether it makes sense or not
The bike also had remains of internal cable routing, but I removed it as it was very coroded.