If you can, stop the order for the ortlieb rollers and get the bike packer plus bags.
You can install d-rings on the straps of the bike packer plus bags and then attach a shoulder strap to one or both bags, making more room for moving in the isles. If you can't find d-rings
I put on d-rings on my bike packer plus bags. It's not as comfortable as a backpack, but, it does make your hands free.
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Feminism is the profound notion that women are human beings.