What about all of our modern conveniences?:
Bulk Food Section:
Most grocery store chains have introduced bulk food sections allowing you to fill up a container as much as you want and pay for what you take. The issue is that most of these stores don't have a system in place to allow the customer to bring in and pre-weigh their own containers to avoid using store provided plastic bags.
Famers Markets:
Some cities have farmers markets. If yours doesn't sucks to suck. Some farmer market retailers will allow you to buy the product without any packaging.
This is a great listen if you don't understand why the responsibillity of waste falls on the companies and not the public/ consumers.