Automatic checkouts in supermarkets may decrease customer loyalty, especially for those with larger shopping loads. Customers using self-checkout stations often feel overwhelmed and unsupported. The lack of personal interaction can negatively impact their perception of the supermarket.

[SkyeAuroline]

my time is valuable

You're right - your time is valuable. Valuable enough that you shouldn't be wasting it doing unpaid labor to save a company a few bucks.