Sidhu's rant went on, "Banks are addicted to fees.  Banks have gotten big, fat and happy on big margins."

Some in the audience groaned, others laughed, while bodies shifted in chairs in reaction to Sidhu's criticisms.

Philip Heasley, CEO of ACI Worldwide, and a speaker on the same panel, said today represents the third big technology shift in banking that he has been through in his career. He ominously added that what happened in prior shifts is that many, many institutions just don't make it.

Still, Heasley had encouraging news for community-oriented credit unions.

"Small, spry, technology focused [financial institutions] will make it," Heasley predicted.

Sidhu, however, wasn't buying that.

"The future of banking is not yesterday," he said. "Small or big, it won't make a difference.  It's about your attitude towards innovation."

Many of the Money20/20 speakers and attendees agreed that wholesale changes are coming soon.

Keynote speaker Matthew Friend, managing director at Accenture, set that tone when he shared survey results that showed how dramatically consumers' behavior around payments has changed.

For instance, by 2020, 46% of consumers do not expect to use cash on a weekly basis.

Another 40% of the survey's respondents said they already use mobile phones to make payments and that percentage is increasing.

One notable prediction was Millennials will decide how we will pay, Friend said.

When asked if Apple might disintermediate traditional payments firms such as American Express, Ken Chenault, CEO of the company and another keynote speaker, said, "I don't think Apple wants to be involved with credit.  They are clear about their core mission."

Chenault was just as blunt about the future of plastic cards.

"I could care less about the payments form factor.  I could care less if plastic goes away."

David Nelms, CEO of Discover, took Chenault's observation about Apple further.

"Successful innovations go through traditional systems. Look at Apple Pay," which goes through Visa, MasterCard and American Express.

He added, "Apple Pay is important. Apple has pulled together an ecosystem. People are excited about this."

But, Nelms cautioned, "It will take longer than people think to get merchant adoption."

As for the looming Apple Pay versus MCX's CurrentC dustup, where the latter appears to prohibit its members from accepting Apple Pay, Nelms took a neutral stance.

"I will not comment on when big merchants will take Apple Pay. But there won't be just one winner. Over time, there will be lots of winners," he said.

Another session that hit on topics of concern to credit unions and other financial institutions was "The Future of the Retail Banking Experience."

Among the panelists were Mike Kelly, CEO of the payments CUSO PSCU in St. Petersburg, Fla., Doug Brown, SVP of FIS, and Brian Pearce, a SVP at Wells Fargo.

"The branch has not changed much since the 1970s," Marilyn Bochicchio, CEO of media company Paybefore and the panel's moderator, said.

So, how will it change?

 "It's mobile, mobile, mobile," Brown said.

Pearce said, "I am sick of the term omnichannel.  Think about the customer first and connect with them as they want. The branch of 2020 will have a smaller footprint. Bankers are coming out from behind teller lines. It's about engaging customers. People like to talk to people."

The credit union branch of the future will be about access, Kelly told attendees at the session.

"Credit unions have tremendous social currency. Credit unions are trying to drive outcomes for their communities," he said. "People don't want a home loan. They want a home for their family."

Money20/20, considered to be the largest conference devoted to payments innovation, attracted 7,500 to this year's event.

The conference runs through Wednesday.