There is such a thing as industrial-grade flash chips, they have better specs and durability. I am familiar with them in terms of using the chips directly in circuit boards, and also industrial grade SD cards. But I bet if you look for industrial USB 3.0 sticks, you will find them. Industrial flash vendors may also have free utilities available that can help you better diagnose failures if you care to.
They will be more expensive, but if you are only buying low quantities you can probably invest another $40 or $50 per device (just my guess) to get more longevity out of it.