Amazon gives non-Prime members free shipping at $35 or more of eligible items. Instead of simply letting users get the product with free shipping, they’ve added a discount that prices it exactly one cent below the $35 limit, while only subsidizing the price with $3.38, which is about half of what they’ll then charge you for shipping.
USPS charges a not insignificant amount for shipping heavy items to Alaska (excluding media mail that frequently takes months and few retailers ever use). If physical stores sold anything at a reasreasonable price (aside from off season fishing /hunting /cold equipment) fewer people would use Amazon.