I just prefer not to take the chance. Besides, many people don't like to leave evidence.
I do it in a disposable 3oz cup (dumped stuff into toilet, rinse the cup 3 times, throw it away), on toilet paper, sometimes in my empty bathtub, or directly into the toilet.
Isaac, that's unhealthy. Just eat it. 
Ew, please tell me why you would like to eat a viscous, salty, and sticky liquid that came out of your snake?