"Overnight, like at our recycling facility, Pier 96, it was like plastic bags went away and they were no longer a problem," revealed Charles Sheehan of the San Francisco Department of the Environment.
People began embracing the concept of bring-your-own reusable bag to the market.
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The law did allow for stores to offer paper or heavy-duty plastic bags that were considered reusable.
But then, because of the fear of spreading the coronavirus, for a short period of time, any bags brought from home were not allowed.
"During the pandemic, we stopped bringing our own reusable bags to the store and that was important to protect public health, both ourselves as shoppers but also the workers at the stores," remembers Allison Chan of the nonprofit Save the Bay.
The problem now is that some people are having a hard time giving up those heavy-duty plastic bags, so much so that they don't mind paying extra to use, in some cases, "lots of them."
I asked one shopper why she didn't bring her own bags. "I'm going to try to remember that," she told us. She didn't even remember paying 10 cents per bag.
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The plastic industry claims these heavy-duty plastic bags can be re-used up to 125 times. That's how, by law, they are allowed to be called "reusable."
"They are not necessarily being used as much as the industry claims that they can be, and they are ending up in our landfills," said Chan.
The shopper we spoke to earlier told us she had a stack of them at the house. She admitted she eventually throws them away.
Once in a while, you'll find people who say they do use them over and over again.
So here's how they are allowed, despite the ban on plastic bags.
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Number one, they have to be at least 40% post-consumer materials and can be reused 125 times, not 100, not 150, 125 times. We have no idea how they came up with that number.
Each bag must be able to carry 22 pounds, at a distance of 175 feet, 125 times. So for the purpose of this experiment, we decided to test one, going to from point A to point B, 125 times. At the very end of our test, oddly enough, the handle broke.
"I do think California needs to take a look at that law, make adjustments and do what it was intended to do which was to do away with all plastic bags whether thin or thick," said Sheehan.
But there is little incentive to do so coming from supermarkets and pharmacies, because they are allowed to keep the proceeds from the sale of each bag.
In 2020, San Francisco knew charging 10 cents wasn't enough to keep people from buying them, so the city increased the fee to 25 cents per bag.
People don't seem too bothered.
"We're in San Francisco and we're in California so we're just used to it. I don't think about it because it's about convenience," said Janae Trevillion, who left happily with her reusable plastic bag.
The Oakland City Council is considering an ordinance that goes beyond plastic bags. It would ben every kind of single-use plastic, such as plastic forks, knives, spoons, that are typically used with take out orders.