Trying to uninstall an unneeded package (e.g., gtk2-tools-32bit) wants to
remove a package that seems to be -not listed as unneeded- needed (e.g.,
libcanberra-gtk2-module-32bit).
> linux:/home/test # zypper packages --unneeded
> Loading repository data...
> Warning: Repository 'openSUSE-Leap-42.2-Update-Non-Oss' appears to be outdated. Consider using a different mirror or server.
> Reading installed packages...
> S | Repository      | Name                   | Version     | Arch  
> --+-----------------+------------------------+-------------+-------
> i | openSUSE-42.2-0 | gtk2-tools-32bit       | 2.24.31-1.1 | x86_64
> i | openSUSE-42.2-0 | libcanberra-gtk0-32bit | 0.30-12.1   | x86_64
> i | openSUSE-42.2-0 | libgtk-2_0-0-32bit     | 2.24.31-1.1 | x86_64
> linux:/home/test # zypper --quiet rm gtk2-tools-32bit
> 
> The following 4 packages are going to be REMOVED:
>   gtk2-tools-32bit libcanberra-gtk0-32bit libcanberra-gtk2-module-32bit libgtk-2_0-0-32bit
> 
> 4 packages to remove.
> After the operation, 5.7 MiB will be freed.
> Continue? [y/n/? shows all options] (y): n

>From my point of view either those packages should not have been marked as
unneeded at all or libcanberra-gtk2-module-32bit should have been marked as
unneeded as well. Since libcanberra-gtk2-module-32bit seems to be actually
unneeded the second option seems to be more valid.

Similarly,
> linux:/home/test # zypper --quiet rm libcanberra-gtk0-32bit
> 
> The following 2 packages are going to be REMOVED:
>   libcanberra-gtk0-32bit libcanberra-gtk2-module-32bit
> 
> 2 packages to remove.
> After the operation, 39.3 KiB will be freed.
> Continue? [y/n/? shows all options] (y): n
> linux:/home/test # zypper --quiet rm libgtk-2_0-0-32bit
> 
> The following 4 packages are going to be REMOVED:
>   gtk2-tools-32bit libcanberra-gtk0-32bit libcanberra-gtk2-module-32bit libgtk-2_0-0-32bit
> 
> 4 packages to remove.
> After the operation, 5.7 MiB will be freed.
> Continue? [y/n/? shows all options] (y): n