Use of DRM-removal software involves at least one level of computer competence above the basic 'turn it on and click' user. I suspect most people who are serious readers are not computer savvy enough to want to try messing around with scripts and plug-in installation. Yes, a few of us can read library books on our Kindles, but not most.
It's back to the same question of adequacy of the device to the task. What you 'can' do and what you might 'want' to do with your device may differ. Personally, I'd buy an inexpensive second eReader if I really intended to rent library books. But I'm not worrying about doing that, I'll just return to the old fashioned way and read the pBook.
There are virtually no books out there that I want to read that are not in pBook format...yet. By the time there are, my K3 will be obsolete or worn out and it won't be a theoretical issue.
(I think we need an emoticon for eBooks not just pBooks.
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