That's news to me. Can you share a link?

I registered three cards yesterday, train-side window at Siam, no line, took about 90 seconds per card, I handed the clerk a copy of my passport, which also included the additional details they require.

https://rabbit.co.th/en/card/

Registration of Rabbit card
Ensure the remaining value stored in your Rabbit card if the unexpected situations, such as lost or stolen of Rabbit card occurred by

Register your Rabbit card
Report lost or stolen of Rabbit card through Rabbit Hotline
Request for refund of the remaining value stored according to the terms and conditions as specified by the Company
Please contact our Rabbit Service Center at BTS Siam Station from 8.00 AM – 7.00 PM daily or BTS ticket offices during working hours by presenting the following evidences and information:

Your Rabbit Card
Original of Thai citizen ID or, for foreigner, passport
Contact details e.g. telephone number or email address
For the applicant who is under 15 years old and having no Thai citizen ID, please present us the official birth certificate or household certification; or the guardian can register instead of the said applicant.
Please also see Terms and conditions