Let's check this empirically. Which cartel-like brands are publicly traded and publish financial reports? We can look at their profit margins next quarter.
Sure, the distributors are different, but I'd assume it's all still Monsanto, Unilever, etc., at the end of the day anyway.
130 basepoints if you use GAAP measures so only ~7% higher margin then but clearly unilever doesn't just have higher costs but is also increasing their margin.