I like the humor.
You're right though, a lot of times this statement is made pretty aggressively.
I work in a library, so I hear this pretty often. I usually say what I really feel, which is that the book is the
content, not the form - hardcover, paperback, audio, ebook - it's all the same book. Well, the exception is if it's abridged - then it's not quite the same book.
Depending on who is saying it at the moment, I sometimes also say that I'm sure that a lot of folks stamped their feet and refused to read anything but scrolls when the present book form came to be. And then I wink.
I just love books, and I'll read them any way I can get them.