Source: when I was 5 I saw my grandmother, RIP, doing that and asked her about it. She explained that as she got older her fingers got drier, and now it's just easier to flip pages that way.
Source: when I was 5 I saw my grandmother, RIP, doing that and asked her about it. She explained that as she got older her fingers got drier, and now it's just easier to flip pages that way.