It's not so much width that changes price, as to how common that specific sizing is. 225/45/17 is more popular in several high-numbers generic family cars vs our stock sizing of 215/45/17 (niche coupes like our cars are sold in relatively much much lower numbers to impact significantly offered sizings/commonality/price), hence i see in 2/3 to 3/4th of cases 225 "of same tire" being cheaper. Now reducing profile height from tire sizing properties as usually happens for tires of similar outer diameter but to fit on larger wheels like 18,19 and so on, commonly rises price, as it's more expensive for manufacturer to design/make almost as much capabilities in lower sidewall height.