the point of advertising is to communicate something. If your kid draws your menu, you signal family values. If you pay a local artist, you signal investment in the community.

If ChatGPT churns out your ad you've signaled nothing. And that's obviously why you can criticize AI for every imaginable reason. That's indeed the difference and why people, regardless of how 'good' your AI art will be, will attempt to hide it, because it defeats the purpose of advertising as such.