More than one brand can own the same name. This is a big ol' pill to swallow for a lot of brands, especially when it's a really visible name, like the name of their company or their most heroic product.
And, listen, I don't even like meeting other Caitlins, so I know how they feel. But given that the ratio of registered trademarks to words in the English language is at the already not-so-favorable 600:1 (don't check my math), businesses should thank their lucky stars ("star," for example, appears in 23,104 trademarked names, according to the USPTO) that this is allowed.
In this month's Etymology, I explored the topic of "samesies" from a trademark perspective.