Privacy, plainly
What stays in the log
This catalog is static pages. There are no accounts, no sign-ups, no forms to fill, and no advertising trackers placed by the catalog.
Like every website, the infrastructure that serves these pages keeps standard technical logs, in this case request records that include IP addresses and user agents, used for keeping the site working and nothing else. Aggregate view counts may be recorded to see which shelves get read.
When a button opens a retail partner's listing, you leave this catalog, and the partner's own privacy terms take over from that point. The link that opens carries a tag identifying this catalog as the referrer; that is how the catalog is funded, as the note in the footer of every page says in pixels.