This is a bit racist imo, or at the least lacking empathy.
It’s a systems problem. Sounds like you (like me) grew up in the 1st world where your country has the proper trash infrastructure. Additionally, the government and schools provided the basic education about why littering is harmful, and society at large understands it in your country. That’s great.
Just because we grew up with this knowledge ingrained into us doesn’t make us “better” people, or better than a filipino person.
Some poor countries have poor trash infrastructure, and they do a poor job teaching the ills of littering to their people. That’s unfortunate, but doesn’t make us “better” than them imo. It just means they are poor and uneducated on certain topics.
Now to answer your actual question, why should someone in oklahoma pay more. I don’t think it’s ethical or even fair for someone in oklahoma to pay LESS for plastic simply because they do a better job throwing out their trash. Cheap prices for plastic encourage additional plastic use. And additional plastic use means more and more plastic will be entering rivers and oceans around the world, which affects ALL of us, including the person in oklahoma. Plastics enter the food chain, via fish eating them, and even through rainfall once they become microplastic in size. Basically, i’m arguing that “outsourcing” the issue to poor countries won’t solve the problem and is just pushing a cost burden onto already poor countries.
A proper solution IMO would discourage plastic production globally, or at least enforce cleanup by the producers of plastic (make them pay for efforts similar to the Ocean Cleanup Project).