"Library Anxiety"- Buying vs Borrowing Books

I was having a conversation with my sister the other day about books, and she told me she has just started re-using libraries to save money on buying books (though she still buys a heap.) In discussing the pros and cons of buying vs borrowing, she professed to a kind of stress or anxiety around books borrowed rather than books bought - ie there is pressure to read a borrowed library book, even if you're "not in the mood" for it within the loan period; and the threat of fines is a real bummer. When I suggested the possibility of "unlimited" loans - even worse! The more library books borrowed, apparently, the greater the stress! Now as a librarian it distressed me to hear that library users feel actual or potential stress when borrowing books (well OK a sample of 1, but I have heard this sentiment expressed by my own borrowers, especially when they have to pay fines). Is there some way of eliminating this stress? Or is this just the cost of having the benefit of free books to read?

Now the DVD loans industry has thought up a pretty nifty way of eliminating at least the stress of fines - eg Telstra's home delivered DVD service lets you keep them as long as you like, no threat of fines, but no new ones until the old ones are returned - but of course they charge a monthly fee so it's in the borrower's best interests to exchange items at a fast rate; and also they can cheaply reproduce popular titles on demand (something libraries can't do - we have to buy extra copies at full commercial cost) - so this model doesn't offer much for libraries...or does it?

I would speculate that 80% of stock on a public library's shelf is stuff that could go out for a much longer loan period and no-one would be terribly disadvantaged (in fact it would be a kind of de facto storage - just in people's houses instead of on library shelves) - it's the 20% of new/popular stuff that we need to keep circulating in its (say) first 2 years of acquisition - so what if we could limit the loan period only on this 20%, but let the rest go out for as long as the borrower wanted it for without having to renew (since we don't have the tool of price, we would have to apply a reasonable limit say 6 months - and borrowers would have to commit to returning consequently reserved items) - the only proviso being that they could only have, say, 10 of these "unlimited" loans at a time. Thus people who were fine averse could happily restrict themselves to these, let's call them, "freedom" loans!! Well I haven't worked out the operational details of how the system could allocate these different loan types to individual items (based on a algorithm of age/usage and reserves pending maybe?) and how we would easily and without frustration indicate the different types to customers...minor details (!??!!) - but I still think this is a cool idea. What a boon for nervous borrowers like my sister, who in all liklihood would continue to self-supply for new and popular titles that she just can't wait for, but who would also like the stress-free freedom of borrowing a wider range of materials without deadlines and fines. (Just eliminate fines, perhaps, like many libraries? But don't you then lose the opportunity for new items to circulate frequently before their popularity expires if there's no incentive to bring them back quickly??) What do you think??