Hmm I often buy 3 or 4 2L bottles and in my experience that is wayy too heavy for paper bags.
And my water, I buy it in 6-packs of 2L, they come plastic-wrapped with a handle so you can carry them more easily. The tapwater in my city is not drinkable.
They can't really help it. It's just in a subtropical climate and ancient piping they need to put quite a lot of chlorine in it to avoid bacterial buildup like legionella which can kill people.
And my water, I buy it in 6-packs of 2L, they come plastic-wrapped with a handle so you can carry them more easily. The tapwater in my city is not drinkable.