At the scale most large studios’ games get printed at, the disk and the plastic casing cost pennies to produce. Shipping is probably the majority of the cost, but even then I wouldn’t expect to cost more than a few bucks, if even that

As for digital, all marketplaces like steam or epic charge a fee per sale, and personal download servers aren’t free and cost electricity and maintenance to keep running.

All together, the actual cost difference between physical and digital distribution is much smaller than you might expect