Spurious English user-dirs created on login

My user-dirs are as follows:

> $ cat .config/user-dirs.locale
> pl_PL
>
> $ cat .config/user-dirs.dirs
> # This file is written by xdg-user-dirs-update
> # If you want to change or add directories, just edit the line you're
> # interested in. All local changes will be retained on the next run
> # Format is XDG_xxx_DIR="$HOME/yyy", where yyy is a shell-escaped
> # homedir-relative path, or XDG_xxx_DIR="/yyy", where /yyy is an
> # absolute path. No other format is supported.
> #
> XDG_DESKTOP_DIR="$HOME/Pulpit"
> XDG_DOWNLOAD_DIR="$HOME/Pobrane"
> XDG_TEMPLATES_DIR="$HOME/Szablony"
> XDG_PUBLICSHARE_DIR="$HOME/Publiczny"
> XDG_DOCUMENTS_DIR="$HOME/Dokumenty"
> XDG_MUSIC_DIR="$HOME/Muzyka"
> XDG_PICTURES_DIR="$HOME/Obrazy"
> XDG_VIDEOS_DIR="$HOME/Wideo"

However English ones (Desktop, Download etc.) are still created on login.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: xdg-user-dirs 0.15-3ubuntu3
ProcVersionSignature: Ubuntu 4.13.0-17.20-generic 4.13.8
Uname: Linux 4.13.0-17-generic x86_64
NonfreeKernelModules: zfs zunicode zavl zcommon znvpair
ApportVersion: 2.20.7-0ubuntu3.5
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Mon Dec 4 13:39:54 2017
Dependencies:
 gcc-7-base 7.2.0-8ubuntu3
 libc6 2.26-0ubuntu2
 libgcc1 1:7.2.0-8ubuntu3
SourcePackage: xdg-user-dirs
UpgradeStatus: No upgrade log present (probably fresh install)