Couscous gets everywhere, no matter how hard you try to keep it contained.
My wife put one in her purse about 10 years ago. Since then, I’m sure we have removed five or six of these bars. It seems to be a permanent purse fixture, eternally at the bottom of the bag.
If you treat leather with respect and care it can hold a lifetime. My leather jacket easily nears the 10 year mark too with thr only damage being near the sleeves.