Most places are the same. If you visit a National Trust estate, there are no handouts with rout guides etc. Caravan Club sites with empty information rooms. I would have thought the Covid risk would be small, but what do I know?.
Individually the risk is pretty small, but the virus can sit dormant on a surface for up to three days and still cause an infection when you touch it - so when you pick up a library magazine you're effectively touching hands with everyone who's touched it in the last three days.
If everyone was compliant with the handwashing / gelling / etc disciplines the risk of handling a magazine would be virtually zero, but you have no way of knowing how compliant those people of the last three days have been.
Add to this that the demographic of caravan site and National Trust users is probably in the older age groups (except me obviously), and I can kind of understand the thinking.
I should say I'm not an expert in virology, but I work for the NHS and I've spent a lot of time over the last eighteen months in meetings with people who ARE experts in virology and they've explained this to us!