IMO, please do not stop this kind of offers. Twice a month would be ideal.
I even put up an alliance message “no pressure to buy the new gems offer” as my alliance is about half P2P and half F2P/C2P.
I was the first to buy in appreciation to my members. Also, it helps those who are F2P/C2P to get more gems as compared to saving like hell. As of now, 16 members bought the offer and for a small fee from those who contributed, everyone now has an additional 480 gems. I don’t really calculate but can anyone tell me how long does it take to get 480 gems collected by F2P? I am guessing a month or 2.
If all 30 members buy that’s an additional 900 gems per person in addition to the 300 gems from the offer. A total of 1200 gems would be equivalent to around USD15.
As long as there are no insensitive people in the alliance that says “WHY DON’T YOU BUY IT?”, why be ashamed of being helped by other members.