True, libraries do not have or hide those books, but you can buy them either ata library book sale or at a estate sale in any educated neighborhood. The tick is more to make kids read them. I read London to the kids when they were little, but further progress stalled when they got socialized into “math is hard” and “classics is boring”. With Twain, I esigned to just quote his witticisms, starting with the most appropriate “when I came back home, I found out that my father became much smarter”.
As to “hiding”, I don’t think this is a deciding factor in yiddishkeit level – Sephardim, for example, dressed like Spaniards or Arabs for centuries, often keeping their Yehadut at home, and survived with more or less same success/failure as Ashkenazim.