There is even a blog post that describes how to use similar method to get all the vendors and product tags as it's impossible to do with API. His code for the vendors seems to be more complicate from the quoted above.
Well this solution likely works, and in one of the threads above it's been reported as the year-proof solution, but there is a problem in my case. The store is password protected so to access this page from within my app, I would need to write a separate authentication code just for this task. So I thought I could query the page through admin API. And I actually could, but page's body_html is empty, so it returns an uninterpreted page content and I haven't figured out how can you request the actual page content though the API.
4. As found on this stackoverflow thread you can also get this straight without the need to create any page templates by querying