Can you snort coffee grounds

Yes - its actually fun and doesnt hurt.

Another opinion:

Snorting coffee grounds puts those coffee grounds in your lungs and in your sinuses. Coffee grounds do not belong in those places and there is no way to know what harm you may be doing to your lungs and sinuses, plus you might end up with a very severe headache from the caffeine going directly into your bloodstream. When you drink coffee, the caffeine goes into your bloodstream much more slowly. But when you snort it, the tissues in your nose allow things to enter your bloodstream much more quickly.