Anyone who spent the last fortnight at these two events will have been struck by the growing divide in the fintech industry: between old and new, physical and digital, Wall Street and Silicon Valley.

Money20/20 has ridden, and driven, the fintech wave to become a monster. In just three years it has grown to such an extent that many of the 7500 delegates in Vegas were locked out of oversubscribed sessions at the huge Aria hotel complex. The owners have already sold up and are preparing to take their idea global.

What is really noticeable, though, is not the size of the thing, but its makeup. Barely a bank to be seen on stages dominated by mobile money outfits, bitcoin startups and tech giants such as Google, Amazon and Facebook (but not, despite being the firm on everyone's lips, Apple).

And the place was awash with money. Stalking the halls, every other delegate seemed to be from a venture fund eagerly searching for the next Stripe, ready to enter the Vegas spirit and make 10 bets in the hope that one will pay off. No doubt some two-man dogecoin team will be back next year, keen to splash some of its recently announced $30m Series A round cash on the biggest, flashiest booth in Vegas, a la BitPay.

There were bankers milling around. They were polite and keen to learn from the upstarts that often dismiss them as relics, but I got the impression that they knew they weren't the star attraction, felt uncomfortable, awed even, in this glitzy, Vegasy world.

A week later and some of us (not many) moved on to the colder, slightly more grownup city of Chicago for the BAI Retail Delivery conference, which has been around for ever but is seeing attendee numbers dwindle.

No glitz here; walking around the exhibition hall I was struck by how many big chunks of hardware were on display – machines designed for dealing with cash (what's bitcoin?). This attachment to the physical world extended to sessions in which branches were declared very much not dead, where video ATMs were lauded as the future. Audience members at Money20/20 made notes on their iPads, at BAI many were using pen and paper.

Does that make the BAI crowd dinosaurs, unwilling or unable to face up to the new digital world? No. Banks just have a whole set of responsibilities that fintech startups don't. They're still looking for inspiration - it was noticeable that the conference's star speakers were from Whole Foods and Adidas.

The fintech market is huge, different parts of it will move in different directions at different speeds. It's easy to mock, depending on your persuasion, the conservative BAI men in suits or the flash Money 20/20 kids, but both showed an openness to new ideas and a refreshing optimism about the potential for technology – be it the blockchain or in-branch iPads – to improve financial services.

If you made it to either event, let us know what you thought.