why is Prompt Product Purchase prompting everyone in the server?

i'm getting complaints from players being prompted to buy products. players are being prompted when someone else clicks on the buy button. i'm using robloxs sample code.

buyButton1.MouseButton1Click:connect(function() game:GetService("MarketplaceService"):PromptProductPurchase(game.Players.LocalPlayer, productId1) end)

this is inside a local script placed in starterpack. i don't understand why this is prompting everyone on the server when someone clicks a buybutton. it should prompt only the person who clicks the button, not everyone. what's the problem here?