I figured there was an appreciable difference. It's not that larger game cards are expensive per se anymore, but Blu-ray discs are incredibly cheap. This was an obvious concern to anyone going in, yet some people (possibly fanboys) downplayed the relative costs of say, a 32 GB game card.
For smaller games like Rime, yeah the publisher will just want to charge whatever the market will bear, but they, like anyone, would notice an appreciable difference in manufacturing costs, even if it's nowhere near what they're charging. They notice a difference but try to charge the most they can anyways, with the fact they'd make less money per unit otherwise as their justification. The fact that there's a different (much higher) fee for third-parties on Switch compared to PS4/XB1 (due to manufacturing costs) will likely preclude too many 32 GB 3rd party titles the rest of this decade. Remember how Nintendo "recommended" 16 GB cards or something like that? There's a reason for that.
Not to same that Rime isn't a cash grab, it is, but there is a price difference that would result in lost profit at the same price as PS4/XB1. Companies don't like that, and they'll always want to price things at the most the market will bear regardless.
Of course physical and digital games should cost the same, and console manufacturers need retail anyways.