Hi @kimmia,
Thanks for sharing this question with us.
I understand your stand on this. The rationale here is to avoid passive subscribers. We want to ensure the user really intends to subscribe. Often, people leave the checkbox checked by default on their Shopify stores leading to passive subscribers, whom have a high likelihood of quickly unsubscribing which negatively impacts your email deliverability in Klaviyo. So we have this additional placed order criteria as a “safeguard”.
Additionally, users who check this box at checkout will log the Accepts Marketing property as true at that time (even if they don’t completed their orders) and you can segment those users within Klaviyo to identify them using properties about someone > accepts marketing = true. Or import them directly into a Klaviyo list via a .csv file from Shopify if you wish.
I hope that’s helpful.