How does an economy run by people voting with money work? How can someone vote for a service they've never used before?

How can someone vote for a service they've never used before? Why does "voting with your dollars" work? If I'm never going to use Apple products, how can I vote against them? Or how do I vote against buying food from a Walmart when I have no other choice?<br><br>Edit: This post was locked due to breaking Rule 1. If you'd like to discuss this post in a respectful manner, please submit a post of your own.