Disclaimer; I'm an academic librarian, so hardly neutral on this subject. As a kid I spent hours in our village library to the extent that the staff got me to help issue books to younger children and to tidy the shelves at the end of the day. My Dad could never have afforded to buy the number of books me and my brother read from that place; and he still goes once a week himself.
Our local council recently spent nearly £8 million on refurbishing the city centre library. It took over 2 years (about a year longer than planned because of problems with the building) and during that time there was no service in the city centre at all. The stock and opening hours were shared around the branch libraries, which couldn't cope with the extra demand. I spent a fotune on coffees because there was nowhere to sit for free in the centre of town and breastfeed a baby; that would have been only one of the many uses I'd have had for the library. Now that it's open, I drop in at least twice a week - every time we're in the centre of town, I take dd to have a play on the story train, and to flip through some new picture books.
It is always busy - not just with people using the computers but revising, reading the papers and magazines, asking about evening classes, grabbing a quick pick, going to reading groups or rhyme time or community group meetings. Last time I was there, the staff were asking readers to fill in a survey on how often they use the library, what for etc. That's a library that's just had £8mil spent on it, having to justify its existence to the new government. One of the key questions was would you rather have a) all the branch libraries stay open, but with automatic issuing machines rather than staff, or b) fewer libraries but with trained staff in each branch. I found this very hard to answer.
It's very important to have qualified staff (MA LIS or NVQ) in libraries; not to disparage the work of volunteers, but they aren't trained in stock selection and ongoing evaluation, cataloguing, preservation, collection promotion, budget management, and any number of other behind-the-scenes tasks that have to be done to keep the service running. A library needs a manager who has these skills; perhaps one manager could be shared between several branches, but those kind of jobs can't be done by volunteers. Volunteers are brilliant for keeping buildings open, answering questions about what's on the shelves, helping with the groups mentioned above. But they can't run a library, and it's not reasonable to expect them to.
My fear is that libraries will end up being essentially big warehouses with the top 100 bestsellers on Amazon on the shelves, automatic machines to issue to readers, but nobody there to actually help people.
And breathe....!