Paddington Station, 8:05pm. A black Audi A4 Cabriolet sits on the concourse surrounded by eight tall tables. Around each of the tables people huddle, necks bent, scribbling on cards. They then post the cards through the side window of the car, which is open a little, behind which a substantial pile of cards is growing.

As you may have guessed, each of the hopeful scribblers would quite like to win the car. The odds are not great, but entry is free, so why not?

From a statistical viewpoint it's not really worth entering. But what each entrant is giving up does have a value, of course. Judging from the boxes of blank entry cards on the back seat of the Audi, presumably in the boot, and in a pile behind the car, the organisers expect to harvest perhaps 25,000 names and addresses from this particular display. I noticed a similar stand at Liverpool Street station last week, and the competition runs until the end of the year, so who knows how many people will surrender their personal data in the forlorn hope that they might be driving a swanky German soft-top this time next year.

Each card asks for name, address, telephone number, date of birth, mobile number and email address. There’s also a simple (a) or (b) question so that the whole stunt can qualify as a test of skill rather than a lottery. Those tempted to leave off a contact number are informed “Your Telephone is your Winning Number!!!”  and that “Winners will be contacted per telephone number”.

Of course at the foot of the card, in 6pt lettering and among other small print, it says, “Our advertising partners may send you written, printed or electronic material or they may contact you per telephone (Delete where appropriate)”. This invitation to delete is not accompanied by any tick-boxes and therefore rather hard to spot if you’re a weary commuter. Presumably you’re supposed to score through the relevant words with a biro if you would rather not be deluged in junk mail and spam.

I wonder whether this card really complies with the Data Protection Act, which demands that the promoter - in this case Fiction Marketing of Hannover in Germany - obtains informed consent from an individual before adding them to a marketing list. If Fiction wants to use the telephone numbers, mobile numbers and email addresses it has collected, it is actually supposed to ask individuals to opt-in beforehand, not to opt out. I’m not a lawyer, but it seems to me that Fiction is sailing very close to the wind.

As for the plucky entrants - well, over-optimistic, insufficiently suspicious people get what they deserve in life. At least one of them will win an Audi.