It's years later but I know that this is a relevant issue now. I have scoured these boards searching for a solution and not found one that isn't expensive and fit my needs. So here's my situation and here's how I solved it for free.
We deliver fish to drop sites - customers' homes/driveways who have agreed to be a pickup site for their neighbors. We want the customer to select their location NOT have it depends on inventory or zip code. So here's what I did...
I used liquid code from this post 'How Did You Hear About Us' and changed the pull down menu title to 'Select Your Pickup Location. It worked. I didn't bother changing the code within for the 'hear-about-us' - I tried to but I am not facile with coding and know I would screw it up. And it worked! Just follow the directions in this post https://shopify.dev/tutorials/customize-theme-ask-how-customers-heard-about-your-store.
Here's the two changes you make from the post's directions: In the snippet you create that you get from Github, change the following lines
Hope this helps!