Online banking, extra validation during online purchases, online government services, validating mobile payment, and more.

And technically it's not government ID but rather organized by banks. There is a government organized one(at least I think it's government organized) as well but only really works for government services.

Banking and plenty of online transactions require it too. Login to government services and anything healthcare, pharmacy, social security and so on. For some there are cumbersome alternatives with two step validation and codes by email or text messages that may or may not work while electronic ID is a thumb on the phone.

Note that it is not a government ID, a lot of correspondence with the government; taxes, health care, ..., is used for it. But it is made by a cartel of seven swedish banks.