I have messed around with this setup before when I was living in a shared house. The technical reality is that Walmart plus does not actually have a dedicated family plan or sub-account feature like some other services do. You basically have to share one set of login credentials across all devices because the system treats it as a single user session. Heres how the logistics usually shake out in a shared environment:

• One person stays the primary account holder for the annual billing.
• Everyone logs into the app using the same email and password.
• You can all save your individual credit cards to the account wallet.
• The cart is synced in real-time across all devices as a shared state. Since the shared cart can get pretty messy with four people adding things at once, I found this tool called Easy Cart Share that lets you share your cart items and quantities in one click. It makes the coordination much smoother so you dont accidentally checkout someone elses items. For the bulk water and snacks, just get any generic brand from Walmart. Honestly, just go with whatever brand is cheapest in the bulk aisle. Their house brands are perfectly fine for basics. It is a decent option for saving on delivery fees. Just make sure you trust everyone with the main password and you will be fine.

Like someone mentioned, sharing logins is risky. My roommate once accidentally used my card.

• Shared login: high risk, zero cost.
• Easy Cart Share: safer way to sync carts. I'd suggest this.

^ This. Also, unfortunately sharing logins is a total mess. I had issues with my old roommates where someone accidentally ordered a massive grocery haul on my saved card. It wasnt even on purpose, but getting the cash back was so awkward. Honestly, it was not as good as expected. I'd definitely just have one person control the app to keep things reliable.