longhairgal- You are probably right that they'll say it's "voluntary" but if somebody didn't comply they would not be viewed in good standing.
There was a talk and watchtower a few months back that said you basically have to be worthy and in decent standing for your donations to be acceptable. Since we are all sinners.....This might be a nice loophole to slide through.
Just don't forget to ask for forgiveness after they collect the forms back to be turned in. LOL