Bug? Different flair costs per person.

my friend and I both unlocked the Mew card a few days apart. We were talking about flair, and we noticed that specific flair options have different costs for each of us. For example, the “Tiny twinkles purple battle flair” costs 18,000 shine dust for me, but for him it only costs 6,000. Conversely, the “puffs battle flair” costs 12,000 for me, while his price is 18,000. I thought flair cosmetic prices were based on rarity/tier. Is this intentional that they’re random per player?