Hotel took photocopy of my Residence card

I am a resident and am on a business trip right now. I was trying to check in into hotel but they told me it is necessary to take photocopy of my residence card. I told them no it is not necessary and I am not going to provide it, however I can show you my number card if you want (still no phptocopy) They told me it is a requirement from the local police and they gather residence card copies of foreigners once a month.

My senpai (a very old guy) was waiting outside, in order to not cause trouble to him I let them take the copy of my residence card but I told them I am going to print out the law that states that they can not copy my residence card.

I have seen that law online once but I could not find its link this time. Does anyone have access to the link or PDF of the law stating that they can not force me to give them my residence card?

Thank you in advance.

by hamabenodisco