Points are awarded based on the country of the referral. For example, if you refer a friend from India, you earn 100 points for each referral. If you refer friends from Canada, you earn 500 points per referral. Also, keep in mind that your referral must earn at least 1000 points before points are awarded.
To see how much you can earn for each country, open the GrabPoints app and tap "Share." Once you're here, tap the "How Much Do I Earn" button to see how much you can earn per country.