Censorship by Postie?

Mrs R has noticed that posties in the West Country are being threatened with disciplinary action (the sack) if they refuse to deliver thousands of BNP leaflets that they claim are "right wing rubbish". It says so in the Times, here

Mrs Rigby's house is listed with the mailing preference service, so she doesn't get much junk mail, although she does get local, unaddressed, leaflets - some she reads, some she recycles unopened. That's the thing Mrs Rigby likes, she chooses what goes into the bin, and why.

Mrs R doesn't think it's up to a postie to decide what she can and can't read. She thinks that, if they could do that, they would be censoring her mail and censoring the information she can receive. She thinks they could limit her choices and influence her personal decisions, according to their own, and she doesn't think that's the right thing for a postie to do.

As Mrs R sees it, if an individual, group or organisation has paid a delivery fee it's up to the postie to do the delivering. Nothing more, nothing less.

She wonders, for a silly moment, what would happen if posties were allowed to filter mail according to any one of their personal scruples, preferences, prejudices and choices, and were allowed to choose to deliver only what they believe in. Would her household get any mail at all? Would Labour, Lib Dem and UKIP leaflets be delivered, would somebody refuse to deliver Christmas cards or postcards describing a delicious meal of lamb, steak or chicken?

Reading the article a bit more carefully, Mrs R noticed this little snippet. It says

The Communication Workers Union claims Royal Mail is breaking a “conscience clause” agreed four years ago which allows staff to refuse to deliver literature they find offensive.

and

The clause says members don’t have to deliver material if they feel threatened or if it is against their personal beliefs.

So, that's all right then! They aren't doing anything wrong!

Actually, Mrs Rigby disagrees, for the reasons she's outlined above, she doesn't think her postie should try to act as her moral guardian.