There is an on-line screen without any sales category assigned. Before upgrade to OSA 7.1 this screen was just skipped, after upgrade domain service plans are shown on that screen.
A screen without any assigned sales category is a type of misconfiguration of the online store.
In 7.0: Online store skips screen without any assigned sales category and selects the next one but customer can see the name of missed screen in breadcrumbs on the top.
In 7.1: Online store shows screen without any assigned sales category and displays all service plans from this online store which are available for additional purchase on this screen.
Online store will be returned to the 7.0 behavior in scope of the request #PBA-80498 ("Domain plans are shown when no category assigned").
If you would like to disable the screen, it must be completely removed, not just categories deassigned.