Your only problem might be from the insurance side in terms of products liability cover as they wouldn't expect you to be selling toasters or something.
You neet to check your lease. The should be a definition / clause called "permitted use" which will tell you exactly what you can and cant sell / do in a shop. This would apply especially in a shopping centre where there may be other shops who want to be the only shop in the centre selling a particular product or giving a particular service.
Was in a chemist before Christmas, admiring the lovely gift baskets, on leaving the shop I seen a staff member making them up. There def was margin to be made when I priced the individual items.
Local hairdresser does gift cards and see on FB page she can do gift presentation in a hamper also with suitable items!.