> Most places that sell online are spending much more than that per customer In percentages yes, as you note. But in raw numbers, that’s insane! Ad placements

> Most places that sell online are spending much more than that per customer In percentages yes, as you note. But in raw numbers, that’s insane! Ad placements (simplified) can be geared towards CPA or ROAS - the former would be towards getting conversions, the latter towards ensuring a return on said conversions. Neither directly implies that you should be spending a massive % of your revenue for it.