Most upsell flows hide the running total until checkout. This one does the opposite - the summary panel recalculates the moment you tick anything, and the bundle discount sits in the same list as the charges, in green.
Most booking UIs are built around the transaction - pick, pay, done. This one is built around the questions people actually have open in another tab while they book.
Destination weather sits inside the flight card, because the moment you're choosing a...