Yes, the process is patented by them [1]. But they've been trying to commercialize it.

It just appears that if you're making something cheap and high-margin like ketchup and putting it into disposable plastic bottles, it's probably more cost-effective for you if the customer throws away an almost-empty bottle and buys a new one, than if you spend more on the fancy coating so the customer can get every drop.

[1] https://liquiglide.com/tech/

Or carcinogenic.