Many people find much greater emotional power and therapeutic potential from Adult Ageplay than just Roleplay or sexual play. For many emotionally-real Innerkids, the craving is for the very realistic re-creation of certain feelings associated with being little and being parented.
Some were abused by parents, and crave some of the powerful headspaces of being safe and loved in someone's strong hands -- others did get to experience what all Biokids deserve, and crave those feelings still, in adulthood. Hence one of the mottos of GI is "For what you miss -- or missed."
So we use the term reParenting to more accurately discuss those in these lifestyles to create headspaces around feeling safely and lovingly parented, as opposed to other flavors of Adult Ageplay which, for some, revolve around lighter Roleplay, foreplay, or other motives.