There are more than 30 Meilianmei supermarkets in Beijing. The services in each store are generally similar, but I seem to have seen the kind of service you mentioned somewhere!
The one in Xinjiekou You can buy recharge cards at Wumart Supermarket and use credit cards, which you haven’t seen anywhere else. Besides, this kind of service is not yet popular in supermarkets, so it should be said that most supermarkets don’t have this kind of service!