The stripes aren't great.
They do look a bit shoddy.
I assume they just use off-cuts for detailing like stripes and the leather used there is not of the best quality.
I used to work in a leather goods manufacturer making items for the likes of Polo / Ralph Lauren and other supposedly prestigious names. As I said, it just looks like they've used fairly poor quality off-cuts for those stripes. We used to make Polo Keyfobs and suchlike with those kinds of scraps.
If I remember correctly, it's called Belly Leather. It can have irregular thickness and is prone to wrinkling.
I've bought leather biker jackets in the past and I've noticed how the manufacturer has put the odd panel of belly leather in there to cut costs.
Your new pair are looking good.