I've referred five people so far, but I haven't got anything. Why is this?

This site doesn't really do any prizes for referrals I don't think. I have referred many people, but Never gotten a reward of any kind. I don't really think it is necessary either, If I like to play a game of course i'm going to tell others about it,Suggesting a game for Prizes would skew any statistical data gathered for advertisement purposes.

I saw something in the settings though about getting an increased chance of getting two scales at once and other things like that, but you can only get them with referral bonuses

Scales at obtained via Nutering Hatchlings and eggs, Ad I guess it may make a bit of a difference, but not enough to fret about. I barely use scales anyway so I guess I never noticed.

In order for the referral bonus points to accumulate, the player you referred must complete certain objectives. Nurturing a certain amount of pets, breeding a certain amount of pets and battling a certain number of times.

After they've completed one of the objectives, you get a point to spend on one of the listed objectives up to a rank of 5.