Would you want to be forced to read a book you aren't enjoying?
We do this with our students all of the time. We buy sets of readers and have the entire class read it. But why? Each student is different and likes different things. The idea of free voluntary reading even from the lowest grades is to encourage choice and enjoyment, not to have the teacher decide which book EVERYONE will read.
Having the entire class read a book has value for reading comprehension and modeling, but it is not free voluntary reading or reading for pleasure. It has it's own value in the classroom, but it IS NOT reading for pleasure or free voluntary reading. It is comparable to a long reading comprehension passage which is learned over the space of a few weeks.
The Reading Zone, Nancie Atwell