Tourism in my own home

Today’s question comes to you courtesy of the Yarden shop in Golders Green. It is…

Why do kosher grocery shops stay open until 11pm? On Golders Green Road this evening, all the ordinary grocery shops (including Seoul Plaza, must go there another day) closed at normal times. All the kosher shops were still open at 10.30pm. One friend suggests it’s because they’re all run by Israelis, who are operating on Israeli time in which they expect we’ve all had a siesta to cope with the *boiling heat* of the day and then want to shop at night. Another friend says: Jews stay up late because we’re too neurotic to sleep. I wonder if it’s because of the lack of a ‘shopping day’ on Saturdays – because you can’t shop on Shabbat. So we have more need of late-night shopping. I asked the girl in the shop but she didn’t know. Any further advances?