The HN crowd is not the typical consumer that shops at Walmart. The typical consumer buys things that they can afford and makes compromises on flavor.
The ethical part won't effect demand just like it hasn't effected demand in the past. The price and taste will help consumers afford more meat. And I'm sure that they would agree that is a noble thing.
The real change is going to happen when people can't tell a difference in taste and Walmart starts selling synthetic meat at a substantial discount to meat. At that point the consumer won't care just like the consumer doesn't care if their strawberry flavored cereal has real strawberries in it.
The ethical part won't effect demand just like it hasn't effected demand in the past. The price and taste will help consumers afford more meat. And I'm sure that they would agree that is a noble thing.