Maybe this proposal is a bit excessive, but Pepsi is a billion++ company, based alsmost entirely on it's brand. They can afford, and expect some reasoning behind their logo design.

Symbolism is all around, in logos, advertising, architecture, etc. Personally I see too many modern designs, even art, merely being 'visually appealing' or 'fashionable', without any reasoning, coherence, references, or anything behind them.