Could this be a possible cause of wheel well rot?

[No Tyme]

I just has my 2019 Ram BH Classic undercoated yesterday by a company that uses Fluid Film. I don't like the rubberized coating as I believe they trap moisture under the coating but the fellow that did the Fluid Film spray showed me this. This is a photo from in front of the curb side rear wheel looking up to the wheel well where it meets the side of the bed. He showed me this stating manufactures put this foam in there for sound proofing but in my eyes I would think it would trap dirt as well as moisture and contribute to rust on top of the wheel well.
I would like to get other opinions on this and if anyone has removed the foam and for what purpose if not for trying to avoid rust in that area.

 

[bigdodge]

It's too prevent vibrations. Keep it spelled in fluid fill out wd-40 and it won't be a problem.

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[PoMansRam]

Most of us who DIY with FF or woolwax remove the black plastic wheel well liners so we can better get at those exact areas, then replace the liners.

I dont think that foam absorbs moisture, but I suppose over time it could degrade and trap stuff that would promote rust.

The front fenders have foam type pads bonded to the insides as well.

 

[Noneck]

Factory Probably trying to fill the little crevice formed there which would collect dirt and salt?

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[No Tyme]

It's too prevent vibrations. Keep it spelled in fluid fill out wd-40 and it won't be a problem.

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I think vibration sounds like a better reason for that foam then sound deadening. Did think about removing it but that is as far as it got, thinking about it, LOL. I don't know if I could get all of it out and if I didn't it may create more of a dirt/moisture trap that what it is now.
Living for at least 1 more winter in Michigan I want to avoid the salt build up if all possible.

 

[No Tyme]

Most of us who DIY with FF or woolwax remove the black plastic wheel well liners so we can better get at those exact areas, then replace the liners.

I dont think that foam absorbs moisture, but I suppose over time it could degrade and trap stuff that would promote rust.

The front fenders have foam type pads bonded to the insides as well.

I never gave that a thought... removing the plastic wheel well liners and spraying underneath there. I did remove the spare tire as I has seen that done before when taking cars over to the rustproofing shop for a dealership.
Thanks for that idea, I have a couple of cans in the shop out back.