What is 'If that weren’t enough branding'?
Buffett shrewdly added in the festive shopping eventthe mid-1990s and today, Berkshire’s shareholders head en masse to the ground floor of the CenturyLink Center. And there awaits a mini-mall comprising booths of subsidiaries selling their goods.
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If that weren’t enough branding, purchases and free handouts are taken home in shopping bags featuring the Coca-Cola logo. Cartoon caricatures of Buffett festoon as many of the products as possible— including boxers, T-shirts and even competing ketchup bottles.

Question

Answer

"If that weren't enough" is a phrase that's always used ironically.  It means that there was already "enough," but nevertheless, something more was (or will be) added.

The reason why the phrase is "that weren't" instead of "that wasn't" is because it's subjunctive.  It's describing an imaginary or hypothetical state.  Many native speakers don't understand this, so they'll instead say "if that wasn't enough."  You'll also hear people say "as if that weren't enough," making it even more clear that they're talking ironically about something that is not really the case (it's plenty, but it's being treated "as if" it weren't enough).

Answer

It's an ironic way of saying, "But that didn't seem to be enough branding......"

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