BOTR: I am not certain of all the full implications but a library card is no excuse.
There is no excuse.
If the WT will disfellowship a JW for joining the YMCA only to use the swimming pool, under the charge of "becoming part of an organization whose objective is contrary to the Bible", (WT considers the YMCA a "false religious organization"), then the lame explanation of becoming an NGO with the UN "to get a library card" is laughable at best.