^ I believe the issue is MAP vs MAF.
Also, I know what you mean in terms of the filter bring redundant but I guess it was for the purpose of filtration. You're increasing air intake but retaining the same amount of filtration, so I supposed the guy who made it figured why not stick a filter on it as well. In California, we've been hitting high 90's-100's consistently. Considering it costs less than $30 in materials(if not including the cone filter), I wouldn't mind doing it.