How to publish a post on a user's wall from a "chat bot"?

Question

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Quite often I have to use the VK API, so I thought I knew it well. But today I came across a bot ( https://vk.com/im?sel=-57208523 ) that can post entries on the user's wall without any permission requests or confirmation windows.
Knowledgeable people, tell me please how it is implemented? Where can you read?

Answer 1

They have an advertising contract with vk.
Large advertisers receive such privileges, in the new year there was a similar large advertising campaign from coca cola.