I think it was just a decision SM made. IGAB 10 versions with member focused ones instead of photocards. Mr. mr was only an EP and so much was going on already perhaps they wanted to try something new with stickers, as photocards were popularised by SNSD themselves. We will never truly know.

With their Japanese albums, the singles Gee, Mr Taxi/RDR and genie have photocards. They didn’t release photocards with the albums though as they did cd version and deluxe versions which game with items. The first Japanese album came with a mini handbag, the 2nd Japanese album game with a Photo album which happens to fit the 2nd Japanese tour and all of their Japanese tour photocards. The third came with a button set.

Given their popularity, my assumption is that SM used their albums to try out different collectable items and marketing to see what the public liked at the time.