I’ve seen them used sensibly for shipment tracking, and such like. They’re great for that.
It’s just a cryptographic enhancement of existing systems, but a nice use of the tech (standardized rather than proprietary too).
One company also used smart contracts to update other systems & such automatically. It was quite a nice system, crypto-based or not.
Personally, as a huge crypto skeptic (and I have worked in the space), I think this kind of use has much more long term utility than the gold rush value stores.
The ticket thing you mention could be useful, but I’ve never seen an implementation that was worth any company (let alone Ticketmaster) bothering with. It “solves” a mostly solved problem.
The marketplace decides what the purpose is. The use case people wanted was an easy way to launder real money into jpegs of arbitrarily set ETH values. Now that the PPP loan and ZIRP era is over, the bottom has fallen out of NFTs entirely. NBA Top Shot was one of the few non-jpeg early succes stories but that's flamed out as well.
Why do this when the current system already handles this? This is no unique usecase.
Once again, crypto is trying to solve problems that don't actually exist while completely failing to address the ones that do.
No, the chain-of-provenance use-case is to prevent people from being able to sell grey-market products while claiming that they're official products. E.g. selling iPhones built out of reconstituted parts from iPhones that were pickpocketed from their owners and then scrapped for parts. (Yes, this is a big issue — Google "my stolen phone ended up in shenzhen" and you'll get a ton of news stories.)
If you (or a retailer) forces the retailer (wholesaler) to provide a chain of digital signatures demonstrating each hand-off of the parts all the way back to the factory that produced them, then you implicitly reject any assemblage of parts where some of the parts were black-market-sourced. Which allows for legitimate refurbishing using legitimately acquired parts (i.e. it doesn't put the Shenzhen phone-repair stores themselves out of business); but destroys the demand for the electronics "chop shops" these stores currently sometimes order parts from.
In this case, a "blockchain" here is an open-public-participation multiparty ledger that tracks ownership of physical goods; with a digital signature inherent to each transfer of the digital asset representing the physical good, which should be done at time of transfer of physical goods. Unlike other use-cases, you really can't simplify the solution — to enable this use-case, you need a system with pretty much all the properties of a blockchain.
Hashing and hash stores are not unique, or particularly original, so really this is just applying common crypto tooling/standards to an existing problem.
It has benefits when you look at it like that.
