Here's a recap of what AR can do for promoting your brand organiccally, without spending money on advertisements.
A good AR filter made by your brand can help people on Instagram, TikTok, Snapchat and Facebook share it with their friends and family, thereby ensuring word of mouth publicity. Your filter could have questions that users need to answer via video or it could have an animation that's funny. If it's engaging, immersive and personalized, it will stay in the minds of people and they will come to purchase your product the next time they want to buy something from that product category.
If your AR effects cater to the right targeted audience, your engagement analytics may see a rise and all of this will happen without spending money for ads.
With social media AR, users can simply share an effect with others, and they might save it for future use. Due repetitive usage by people with a high follower count, especially influencers, your brand could gain high visibility.