Marcel snores, and it's so flippin' cute
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However, it means some of the same things that snoring can mean in humans. As in, something structural is wrong and "flops" out of place, causing partial obstruction of the airway. Some dogs have elongated soft palates, inverted sacules, or stenotic nares. Dogs with allergies sometimes snore too.
One of the concerns, for example, with elongated palate is that over time...with the flapping around, it can actually weaken *all* of the muscle structure in that area...causing the actual problem to worsen, and also causing secondary issues in the surrounding structures.
If concerned, you could ask the vet to start with a sedated exam to see if anything can be observed in the structures at the back of the throat. A scope could be done too...but that's more involved.