13yr boy hanging outside school till after 6pm for parent pick up

[Pepp1]

is it ok for a 13yr boy to hang around outside school till after 6pm for his parent to pick him up after work and bring him home? (he has relocated and now lives further away).

My child won't come home because the 13yr will be left on his own. This is causing me issues because 1st, I don't think this is acceptable and 2nd my child then is sometimes making his way home in the dark after 6pm himself.

Am I being an over protective parent or is this wrong?

Its happening 2-3 evenings a week at the moment.

Can someone please advise?

Tell the school. You must.

People aren't replying that this isn't ok because of the boy's age. Adults would worry about other adults waiting alone for 3 hours because it must be very boring and uncomfortable because of the weather and the fact that it's getting darker sooner. Also what does he do if he needs the loo? Even if he goes before leaving, it could be hours before he gets to go again.
If this was my child's school then they could walk 10 minutes to the warm council library but I'm assuming that the school isn't close to amenities like that. Our school library is also open until 5pm and is popular with the younger years who don't want to be home alone until their parents get back from work.