On the pro-side of the paper folded hot-dog style to divide positive from negative, is the novelty. The excitement of being part of something new, feeling more attractive simply by proximity to something that agrees with you, will be seen with you, that you can show to your friends and which will garner compliments, theoretically.
Then again, it’s uncomfortable. New shoes mean new terrain, revisiting the old but carrying yourself in a different way to accomodate the addition. It means breaking in the unfamiliar, investing time in something that, inevitably, will reach its end, natural or otherwise.
On the other side, maybe the shoes will become the pair, the pair that day by day fold and mold to you (or do you change?), that become almost part of you. The wear is there, but show the strains of adventure, braved together.
Or is it just content derived from comfort? Will it soon transform into a bitter resignation, ignited by a world seemingly full of potential new (better?) shoes? At what point do you start to blame your once faithful companions for your decision to settle? Or is this it — the shoes to end all shoes, your best chance at happiness? You only technically need one pair, but can they be expected to fulfill all of your needs? When do the extras become distasteful?
Then there’s etiquette. At what point is it acceptable to discard the remnants of a once beloved pair? Should they be losing pieces in public? Or should you stop before all is lost, store them away in a hidden place, where they can be found, but only resurface in fits of nostalgia?