This was specifically forbiden by Google eons ago. You could not create an ad with Pepsi in it, unless you were Pepsi. What we have today is intentional, they

This was specifically forbiden by Google eons ago. You could not create an ad with Pepsi in it, unless you were Pepsi. What we have today is intentional, they have the system to prevent this but they choose to no longer use it. It might be that your own ad with your own brand in it is way cheaper than the competitors ads with your brand in them. Maybe they just want some money from you even when the user searched for your brand specifically. Maybe they want to train users to always click on ads (hard no to when the ad is exactlly what you searched for)