We're excited to give Facebook users the confidence that when they purchase Facebook Credits or receive them as a gift, they can spend them in any game on Facebook, wrote Facebook marketing manager Deborah Liu this week.But, perhaps expectedly, not all developers think mandatory adoption of Facebook Credits, and the 30 percent revenue Old School RS Gold cut that comes with the system, will be beneficial.At this week's Inside Social Apps conference in San Francisco, Liu was asked to address concerns from small developers about Facebook Credits. She responded by saying, Every single day we know developers get to choose between our platforms and another platform. She was reportedly met with laughter and jeers from the industry audience.With 500 million users on Facebook, choosing another platform -- even one without a 30 percent revenue share -- just doesn't make financial sense for many developers, as the reaction to Liu's statement seems to show.With Facebook as the overwhelmingly dominant social network, some game developers now feel stuck between staying with Facebook and its new, mandatory payment system or gambling on another means of delivering their games. Likely, most won't take the gamble. Making Facebook Credits mandatory in games on the platform is likely to spook many developers, Kavin Stewart, VP of product and co-founder of 44-person Ravenwood Fair developer Lolapps told Gamasutra. His company has already adopted Facebook Credits. It's natural for people to look at the short-term, seemingly obvious 30 percent hit to their bottom line. Runescape Account But the startup Lolapps, founded in 2008, thinks in the long run that having a universal currency system will pay off. What these [detractors] are failing to take into account is that less friction in user payment and more brand trust in payments will greatly increase people's desire to spend, he said.