I don't think the Discovery Bay Park n Shop is any better or worse than any other in Hong Kong, supermarket shopping in general here, sucks very badly. Watch your stress level rise lol. Shopping in HK is unique, not that i care anymore, I gave up trying to work out why people cant walk straight, why they don't watch where they are going, why they speak so loudly, and funny enough nobody is inspired to get violent toward each other as a result. Most surprising, back home some of the behaviour would get you hurt, especially the HK favourite, line jumping....
Anybody who has ever shopped at a Carrefour in Paris or City Centre Dubai, knows exactly how badly Hong Kong blows, for anybody who actually shops in person. At least shopping in both locations was pleasant, uncrowded and just nice, fun even. 
Rule of thumb in our self shopping house hold is( I refuse to get a maid), to never shop on the weekends, because the super market just gets insanely busy, during the week at off peak times is best.
As mumto2 has lived and shopped in Japan, basically HK is the complete opposite when it comes to retail and street side etiquette lol. Anything goes here, and if people walk in front of you, just peel their shoe off with the toe of yours and give them a flat tyre... It will make a frustrating thing fun
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