As long as you don't do anything truly bad when shooting your shot, the worst that could happen is some mild embarassment. Which is something you have to be prepared to endure when putting yourself out there.
Competing with the likes of Amazon can't just be done in software alone. Each merchant would need to handle actually shipping out products themselves, that's the real barrier to entry. And what of consumer protection, how do you keep this platform from being overrun by scammers and bots?
I might be pushing the definition of 'spending' a bit, but I'd say Kirby Air Ride(rs)' City Trial fits this bill. You spend the City phase gathering as many stat boosts as possible, then use your build to compete in a Stadium event. Then you queue up for another match where you get to start over and do it all again.
Solar Sensor? It's been a childhood dream of mine to be able to play Shin Bokura no Taiyou: Gyakushuu no Sabata with both the translation patch and the Solar Sensor at the same time.
They're kind of just really damn bad at being currencies. Transaction times and fees make them too difficult to use for anything short of money laundering. But actually decently suited to that one purpose since other forms of laundering are usually even more expensive.
Even worse though is the deflationary nature also disincentivizes ever using them as currency. They're instead being treated as speculative assets, people buy crypto not because they actually want to use crypto, but because they expect to sell it to another bagholder later. But of course the only way to profit off crypto in this way is for someone else to lose. And yet people still try to pretend it's a currency even when no one will ever use it as such, because it sounds more legitimate that way.
And this in turn has made crypto an incredibly attractive target for scams and grifts. Pump-and-dumps are everywhere, but even when people know this they still try to get in hoping they'll be the one to win this time.
Crypto really is just a solution in search of a problem, and every now and then you'll see cryptobros insisting they have the next big thing in NFTs, smart contracts, whatever bullshit they're pushing next. But none of it has ever been anything more than a vehicle to try and find a new way to rip someone else off. They just need to convince you they have something to sell here so that you'll be the next sucker.
Bitcoin has been around since 2008, and in all that time, it's still not amounted to anything more than one big grift.
The message is make handjobs, not war. That's how we'll achieve peace in the middle east.