Hi,
I have frequently seen driving school cars with passengers in rear ..... I assumed the instructor was aiming at maximum utilisation of car and time.
I taught my wife to drive in a Sunbeam Talbot 90 on Penang. One day we picked up two Norwegian (?) hitch-hikers. Soon after we were stopped by two Chinese policemen who didn't speak English. I think they were telling us that learners were not allowed to carry passengers. Whatever, Barbara threw a wobbly, after which their sign language seemed to indicate that they were happy for us to continue. Years later, she did the same to a UK police sergeant while stanfing in middle lane of M4. Sgt told me to "get my wife out of his sight and he would say no more about this". Seemed too good an offer to refuse. Oh yes, she had one professional lesson in UK, passed test first time in a car that she drove for first time on previous day. It snowed on January 1st 1970. I still wake up screaming.
602 PS Learners are not alowed to tow a trailer, but everybody already knew that.