I surmise you are being sarcastic, but this is a reasonable question. There are plenty of liquor stores which seem to be of greater value (and likelihood to generate future revenue) than whatsapp.
All they'd have to do is start running ads to show how absurd what you just said is.
I find it laughable that in 2015 people are still claiming companies strategically delaying monetization have worthless businesses. They care about long term growth, not money in the hand. See Facebook and Twitter. And a bunch of other companies.
I don't disagree at all, but I don't see even the advertising or collection value of whatsapp. Even if it does exist, it is not similar in kind to facebook or twitter, where you have a captive audience using a stateful application suite.
Whatsapp seems to have less revenue potential than products which have already shown an inability to find the black, such as AIM.
If they started charging a monthly fee to use the app enough people would stick around that they'd be able to buy a sizable % of all the liquor stores in the USA. How many, I don't know. That would make an interesting interview question.
Edit: gonna try it
My city has 500,000 people. I'm going to estimate there are 500 liquor stores here. So that's 1 per 1,000 people. The USA has 330 million people, thus 330,000 liquor stores.
A liquor store is probably worth about $50,000. Thus, they are all worth $16.5 billion.
Whatsapp has 800 million MAU's. If 2% of them convert to $10 a month paying customers, that is $160 million per month.
They could run that business much cheaper than the current one, so say 50 employees at $10k a month each. $500k a month. Double that for hosting and rent etc. $1 million a month.
Those costs seem way too low in relation to revenue so let's just bump that up to 50% of revenue. $80 million/month.
So $80 million per month profit. Or over 2 liquor stores per hour, 24/7/365. In about 15 years they'd own every liquor store in America.