Tea Lottery

I don't know how I got this email, but I was just invited to sign up to something called Tea O'Clock. They say:

At a time set by you, Tea O'clock will find out who in your office fancies a cuppa, compile your team's order and decide whose turn it is to make the drinks. It's fun, it's free and above all, it's fair!

The website makes clear:

we’ll send out an email to a randomly selected person telling them it’s their turn to make the drinks... It's like a national hot drink lottery where everyone's a winner.

See also their FAQs here.

It's a bit useless to me directly, since I neither work in an office nor drink tea; but I'm always interested to see examples that demonstrate people regard lotteries/random selection as fair means of allocation, even if this example seems confuse randomness with taking turns, which is plainly a different allocative rule.