There are texting packages in European contracts as well, particularly in the more competitive markets in North Europe, but one reason to prefer WhatsApp is roaming: in the US, you can use your texting package all over the continent, but in Europe, you couldn't - whenever in a neighbour country, sending an SMS or an MMS could be very expensive, and what's worse, the price is unpredictable or even scammy.

So it was better to use wifi and WhatsApp to communicate. Once you'd fixed your net access, you could be sure of cheap easy text communications.

The EU roaming pricing law has now fixed the original cause, but it is too late to change people's behaviour.