Price is never determined by cost, but by the market. If Fujifilm believes their customers are willing to stomach the price hike, then why not? The firm will seek the best pricing to maximize its profits. Even though higher price means lower sales, if Fujifilm believes the price differential may well more than compensate the sale loss, then price hike!
To elicit sympathy and support from their customers, price-hiking is always advertised as covering raising manufacturing cost. But the truth is, unless market forces them, the company never drops price when the manufacturing becomes cheaper.
If the market price of certain films cannot cover their manufacturing cost, Fujifilm will stop making it. Actually it just did for several in the past years.