(NewsNation) — Two online gaming marketplaces have purged titles with adult-only content in recent weeks, citing regulations from their websites’ payment processors — and users aren’t happy.

Indie-focused marketplace site Itch.io has moved to deindex all not safe for work content from its browse and search pages, according to a Thursday blog post from creator Leaf Corcoran.

“Our ability to process payments is critical for every creator on our platform,” Corcoran wrote. “To ensure that we can continue to operate and provide a marketplace for all developers, we must prioritize our relationship with our payment partners and take immediate steps towards compliance.”

Payment processors are third-party companies that handle payments made online, and the most widely used are PayPal and Fiserv. The processors work alongside credit card companies like Mastercard and Visa, which have had strict guidelines against purchases of “unauthorized and illegal adult content” on websites for years.

Major online game marketplace Steam is also under fire for recent guidelines requiring uploaders to fall in line with processors’ standards.

Valve Corporation, an American video game developer that owns the marketplace Steam, warned uploaders not to share content “that may violate the rules and standards set forth by (its) payment processors and related card networks and banks, or internet network providers.”

As of Friday, more than 80,000 have signed a petition against Mastercard, Visa and groups who campaign against adult-only content.

The petition contends that changes to policy allow credit card companies to police what people are buying “not because they’re illegal, but because they offend the personal values of executives or activist groups.”