Any use for grey bumpers?

My pup comes back from training next week. I placed an order of 16 neumann & bennet jumbo (3"x12") bumpers from Gun Dog supply last week. They didn't have white for some reason, but the grey ones pictured looked nearly white, so I ordered them, and it turns out they are WAY darker of a grey than how it was pictured. I'd call them dark grey. I placed an order with neumann & bennet directly for 16 white bumpers, so I'm getting those no matter what. My issue is whether I should return the 16 grey ones. They cost me about $90, with Gundog Supply's free shipping, but I'll end up having to pay somewhere between $20 and $30 to ship them back for a refund.

Should I bite the $20-30 return shipping and get my refund back, or do you think there's some use for dark grey bumpers (keeping in mind I'll also have 16 white ones as well)? I was thinking they could come in use when there is snow on the ground, but I'm new to training, so I just don't know. Thoughts on that?

I've also heard darker colored bumpers, dark grey or black, show up better in water to a dog than white bumpers when there is glare on the water. Any feedback on the veracity of that is greatly appreciated as well.

Thanks!

Any use for grey bumpers?