Speaking with GI.biz, a PETA spokesperson said the organization uses games to raise awareness in people who "may be turned off by more direct appeals." It originally turned to games to attract young males, but has since learned the demographics are much wider. The group believes Majesco took the parody in the way it was intended, which seems like a reasonable assumption considering the publisher's lighthearted response. Despite all the joking, PETA does hope that Majesco makes a Cooking Mama: Vegetarian Kitchen "one day."
Source - PETA: We'll keep using games "to spread our message" [GI.biz]
Source - Cooking Mama Responds to PETA Parody [PETA]