If your child is genuinely healthy and there are no complaints about posture or development, preventive massage is more of a safety net than a necessity. I wouldn't rush into a course just based on your pediatrician's word - it's better to find out specifically what they find concerning (even if it's just in the early stages), or ask for a second opinion from a neurologist or orthopedist if you want to be extra cautious.
At two years old, kids are growing and developing actively, and sometimes doctors recommend massage to prevent flat feet or mild muscle tone imbalances - it's not always useless, but it's not critical either if everything's fine. The money you save can go toward things that definitely help: active play, activities that build coordination, good sleep and nutrition.