Currently on Roblox, if you have a paid access game, only people with Edit and Testing access can play the game for free, anyone else would have to buy it for Robux.
Many gaming platforms that offer games for money have a Gifting feature, which lets one player purchase and then gift someone else a game. If this feature was on the Roblox platform, it would allow for better growth of paid access games by people gifting the game to their friends who don’t have the Robux to purchase it.
On Steam (and I’m not sure if this is applicable to other platforms), developers of games can give out access keys to their community, either for testers (but this feature would be redundant on Roblox), or as giveaways. Giving out access to games to non-testers and non-devs could be a great way for developers of games to grow hype around a game, as players could receive the game for free if they win it in a giveaway, encouraging them to be active in the game’s community.
Steam also has library sharing, allowing one player to access another player’s library (not sure about the exact requirements, but multiple accounts on the same device do have this). This could also be a feature on Roblox. Players could send an invite to a friend to play the game for free for a certain period of time, which could also help the growth of paid access games.