Best way to test consumer reactions to sustainable packaging changes?

Surveys are fine but pair them with a shelf intercept study or simulated shelf test — seeing the actual package in context tells you way more than abstract questions. Tools like Hotjar or even a quick Qualtrics conjoint (swap recycled vs. standard packaging as one attribute) can quantify how much shoppers actually care vs. just say they care. In my experience, the 'say-do gap' on sustainability is real, so behavioral data beats stated preference every time.