There are several ways that you can earn donation credit and site rewards without actually donating anything. Detailed below are a few things you can do and their corresponding benefits.

Refer a Friend
Get a friend to join the RPG, mention that you referred him or her in their join form, and then if they remain active for 10 updates, you will receive $5 in donation credit, and then both you and they will receive +100 all stats, + 500 zeni, and +10 DP.

Sign up for Robinhood
Sign up for the Robinhood stock trading app using my referral link: https://join.robinhood.com/alexh1102 and then complete the sign up process (it's a legit brokerage so you will need to use real information but it is completely safe - Google more about it if you are concerned). You don't have to spend any money on this for the referral to count. Not only will you get a free stock yourself for using my referral link (Chaos got a free share of Microsoft worth approximately $335 at the time of this writing - ask him!) but you will also receive $10 in donation credit, +500 all stats, +500 zeni, and +25 DP.

Follow me on Twitter
Follow me on Twitter @WiseAle2 then PM me the name you followed under and you will receive +200 all stats as a bonus.