1) Enclosing vote yes propaganda with the ballot form
The package contains a letter from the Union National Secretary and one from your Branch Chairman outlining why the Union is recommending a particular vote. That's been normal in any ballot I've ever received forms for.
2) Counting the votes themselves
Some ballots have more stringent requirements prescribed by law. If this one doesn't why would you go to the extra expense ?
3) Have marked each ballot paper so that it identifies the voter
The forms have been individually and rather crudely numbered with a hand stamp. There has to be some basic security to stop you photocopying 200 votes and sending them in.