Why are the Asia stores in Basel shut Sundays now?

After trying to go to the Asian stores on Sunday two weeks ago we found out that A. Chau At SBB, the New Asia Market and the little hole in the wall place on Claraplatz are all now closed on Sundays apparently.

Does anyone know what's behind this?

All these stores used to be open on Sundays and were a valuable thing to have. Anyone know why they're all mysteriously shut now?

Could they have families? Adjusting to the Swiss way? Have to pay more to be open?

It's a small community; I think a small group of Chinese/Thai/Vietnamese own and/or run and/or work in most of the Asian supermarkets and restaruants in Basel.

Once one decides it's not worth working on Sunday then their families all stop wanting to work and the other venues lose their staff. Pretty quickly, you end up where we are now; with them all shut. Luckily Saigon Moon is still open (most) Sundays.

The Sri Lankan place behind Burger King near SBB (run by Sri Lankans or Indians, I'm not sure) is not affected by this so is still open