I find it a lot harder trying to convince everyone to change versus forcing everyone to change through policy and enforcement through government.
Other options can be applied, but only really if we don't agree, usually due to personal choice being relevant (some drugs, prostitution, seatbelts and helmets) or non-linear effects in both the utility and externalities (most pollution). Or both (cigarettes, alcohol, sugar).
The "responding to demand" is a complete cop-out. Stop blaming the consumer for the actions of the greedy.
I wouldn't be surprised if the consumer very often isn't even aware of the sources of the materials for a lot of the stuff they buy. And it doesn't help that the consumer is all too often worried about stuff that immediately affects them, leaving them no time or energy to worry about stuff that's they're not immediately aware of.
It's like blaming the consumer for the ridiculous amount of plastic corporations use for packaging when that's all that's available 99% of the time.
Oh, that's a huge pet peeve of mine. In some places I lived it was impossible to buy produce without plastic bags because the stores force you to use their own bags. Also you have to put different vegetables on different bags. Otherwise you can't buy.
Sure one can argue that I could just boycott all the supermarkets in my city, but those people forget that I also have to fucking eat.
Agree about the plastic though, that stuff is almost impossible to avoid.