I thought the point of making them like this was that they technically are reusable, so they can sell them (to people who for some reason keep buying them and throwing them away!) in places where disposable vapes are banned.
The bag laws have done nothing but increase the consumption of plastic, since stores still go through nearly as many, but they’re 5x thicker now.
5x thicker is still a net win.
And it was less about reducing plastic consumption and more about reducing plastic pollution. 1000 tonnes of plastic in a landfill and incinerators (because the heavier bags are more likely to be reused even just as bin bags) is better than 200 tonnes blowing around and decaying into environmental microplastics.
In terms of total plastic consumption, 8 billion plastic bags (what the UK used before the charge) is maybe between 20000 and 40000 tonnes depending on thickness. Which is pretty minor on the scale of plastic usage considering how much plastic crap and packaging was and still is used.