When Alice Walton, heiress to the Walmart supermarket fortune and the the 10th richest woman in the United States, opened a spectacular fine art museum in her home town, she might have expected plaudits and gratitude. It hasn't quite worked out that way.

The long-awaited opening of the Crystal Bridges Museum for American Art in Walton's home town of Bentonville, Arkansas, has provoked mixed reactions. Some have celebrated the unveiling of a significant new private art institution, but many have criticised the decision to spend $1.4bn of company and family foundation money as the retail colossus cuts back its workers' benefits.

Protesters at the museum have informally joined forces with the Occupy Wall Street camps across the US and point to growing ties between the Occupy movement and established trade unions.

The museum, which opened last weekend and features a survey of American art from Benjamin West to Georgia O'Keefe, from Norman Rockwell to Andy Warhol, and from Joan Mitchell to Walton Ford, has also come under criticism from within the art establishment for both inflating values and buying masterpieces from impoverished art institutions without giving local institutions a chance to match Walton's offer.

While historians point out that this is little different from 19th-century robber barons such as Henry Clay Frick and Andrew Carnegie amassing vast collections of European art and bringing it to America, the prospect of hundreds of masterpieces in rural Bentonville, two hours' drive from Tulsa, is still controversial.

Walton, at 62 the youngest of Walmart founder Sam Walton's four children, started buying specifically for the project in 2005. The Moshe Safdie-designed institution, which sits in 120 acres of dogwood trees and trails minutes from downtown Bentonville, already has 440 works on display and 800 in storage.

"We set market records for very few pieces that we purchased," says curator, David Houston. "But there is latent criticism from an east coast elite that bringing a famous painting like Thomas Eakins's [$68m] Gross Clinic to Arkansas is itself an act of cultural vandalism. We're bringing art to the public, but it's a different kind of public, and there are social and political connotations to that."

In the week since Crystal Bridges opened, it has already seen 5,000 registered visitors. "Sheer curiosity and hunger for an institution like this bears out Alice Walton's vision," Houston says.

Ben Waxman, spokesman for the union-affiliated Making Change@Walmart, said: "Opening a huge, opulent museum in the middle of nowhere while the company is cutting health insurance for its employees is troubling. It sends the message Wal-Mart doesn't care about them."

The issues of wealth distribution that have brought art into conflict with the labour movement at Crystal Bridges have also been on display at Sotheby's during the billion-dollar modern, impressionist and contemporary sales earlier this month in New York.

Since August, when Sotheby's dismissed 43 unionised art handlers, its salesrooms have been besieged by Teamsters union members, bearing an inflatable rat and a fat cat banker with a cigar in one hand and throttled worker in the other. "The company is having its most profitable year in 267 years and they locked us out in the middle of our contract," said Teamsters member Phil Cortero. "Sotheby's represents the richest people in the world. When you lose your shirt down on Wall Street you come and hock your stuff here."

Increasingly, the Teamsters are joined by Occupy Museum activists, chanting "We are the 99%!" They protest that the multimillion dollar art handled by auction houses is used to maintain and transfer the wealth of the 1%.

Outside Christie's, which is not involved in the dispute, Los Angeles property developer Eli Broad, one of America's wealthiest men, confirmed as much to the New York Times. "People would rather have art than gold or paper," he said.

OWS Labor Outreach member Mike Friedman said that Occupy had no problem with the art itself. "But at a time when we're seeing cutbacks in health and education spending, we're seeing the transfer of wealth by way of tax cuts and subsidies to an elite who use excesses of that transfer to buy these magnificent works of art."

With the end of the Zuccotti Park sit-in, Occupy says it plans to initiate focused protests against cultural institutions associated with big Wall Street donors. It has singled out Lincoln Center, home to the New York Philharmonic, the Metropolitan Opera and New York fashion week, which is financially supported by Tea Party funder David Koch.

Back at Crystal Bridges, Houston argues that it will take years to see the full effect of how the Walton family has used its wealth. The family foundation is active in a whole variety of charitable activities, many of them educational, he says. "Their intent is not to create a shrine to an individual or even a family. Their goal is to create a tremendous cultural resource in this part of the world."