There is absolutely an advantage to gaussian splats to traditional geometry in both traditional offline and also realtime rendering contexts. Instead of thinking of gsplats as some sort of alternative representation, we should think of it is a new form of importance sampling; however instead of prioritizing ray saliency versus illumination, we should prioritize spatial density versus visual contribution.
I actually worked on this problem, more generally, at ILM with Pat Conran ("Retaining a Surface Detail", 2012).
Gsplats move us away from the strict intersection checks and poly rasters to the a probabilistic domain. A high-poly mesh can waste computational budget on surfaces that contribute little to the final image's fidelity. By treating the scene as a collection of anisotropic kernels, we are performing a high-dimensional optimization of where bits of information should live to minimize reconstruction error. If we prioritize perceptual saliency, we can think of gsplats as a sparse, cached representation