1. A system for facilitating satisfaction of costs for in-game actions through activities external to an online game, the system comprising: one or more processors configured by machine-readable instructions to: execute an instance of online game, and to implement the instance of the online game to facilitate presentation of the online game to players on client computing platforms, such presentation facilitating participation of the players in the game through the reception of commands from the players through the client computing platforms, and executing corresponding actions in the instance of the online game, wherein the actions are associated with costs such that completion of a first action in the instance of the online game in response to a command received from a first player requires satisfaction of a first cost associated with the first action by the first player and completion of the first action in the instance of the online game in response to a second command received from a second player requires satisfaction of the first cost associated with the first action by the second player, the first cost including one or both of time and/or expenditure of a virtual item; and effectuate presentation to the players of sets of proposed activities for the individual actions in the online game that can be performed by the players instead of satisfying the costs of the individual actions for completion of the actions, the sets of proposed activities including a first set of proposed activities that is specific to the first player wherein individual activities within the first set of proposed activities are associated with a given benefit amount specific to the first action such that a first individual activity within the first set of proposed activities is associated with a first benefit amount specific to the first action, and a second set of proposed activities that is specific to the second player, the first set of proposed activities including activities external to the online game that can be performed by the first player instead of satisfying the first cost for completion of the first action and the second set of proposed activities including activities external to the online game that can be performed by the second player instead of satisfying the first cost for completion of the first action, wherein the first set of proposed activities specific to the first player includes at least one proposed activity that is different than proposed activities included in the second set of proposed activities specific to the second player; receive selection of the first individual activity from the first set of proposed activities by the first player; obtain an indication of successful performance of the first individual activity by the first player; and complete the first action in the instance of the online game in accordance with the first benefit amount for the first player responsive to receiving the indication of successful performance of the first individual activity by the first player.