Curve Blue is typical choice for new customers, rewarded in Curve Cash program with 500 points = 5 GBP. By referring Curve card anyone can get next 5 GBP - everyone here knows it.It is one of the perks which can convince new users.
But you may not know that Curve marketing organized so far few promotions offering referal code which will give new user 10 GBP. One example of it from summer 2019 is here: https://www.pepper.pl/promocje/premia-10-na-start-i-wszystkie-karty-w-jednym-miejscu-at-curve-157953 and it is not the last one, you can easily find others.
So how can I refer card to a friend or write on my blog about it, saying “it will give you 5 GBP” as friend can answer “you stupid, I found a code for 10 GBP, do not fool me”. I cannot compete with that, not that way. Marketing division treats participants in unfair, dishonest manner, giving special, “better” codes to some bloggers or sites.
This way referral program is not going to work. If you want to reward someone, please do behind the scenes, do not spoil the program by unequal treatment of some participants.