config values in YAML are not where expected in context

[c094728]

In my func.yaml file I have this

name: crawl
version: 0.0.4
runtime: node
entrypoint: node func.js
type: async
format: json
timeout: 1800
config:
  ALLOWED_HTTP_METHOD: POST
  FN_SERVER_HOST:  http://someurl.com
  FN_TEST: test value
idle_timeout: 3600

In the context I receive when running
ALLOWED_HTTP_METHOD is under ctx.config.properties.ALLOWED_HTTP_METHOD
which is reasonable.
but the other two config values I added show up under
ctx.payload.server_host
ctx.payload.test

different path, lower case and removal of FN_
is there a reason this is so obfuscated?