How so? Nobody forces you to join such a group, or is trying to hide the fact that it's commercial. If I booked a vacation with some company and they offered m

How so? Nobody forces you to join such a group, or is trying to hide the fact that it's commercial. If I booked a vacation with some company and they offered me to join their WhatsApp group specific to my destination I see nothing wrong with that. The reason we don't have that here is probably that it's too expensive. In China you can hire someone for next to nothing to monitor some WeChat groups and have them answer frequent questions or extract potentially useful new information from other users conversation in that group. Shouldn't be too surprising and if you don't want this, don't join. Like when you're uncomfortable with sharing random recordings from your home with Amazon, don't buy Alexa.