I'm also a first year PT student and I completely agree that some of the professors are very limited in their scope of knowledge, that's besides the point. 80g a day would be enough to for a healthy lifestyle, but not for an athlete or weight lifter. The large amounts of protein can have an effect on the kidneys (as far as making them work harder but won't really cause kidney damage) but that is why a large fluid intake is recommended with increased protein.
It's also my understanding that excess protein, which at that point has been broken down to amino acids, can be technically stored as fat. It is possible for fat cells to take up glucose and amino acids and convert them to fat molecules. However, the conversion of protein (or even carbs for that matter) is much less efficient than just storing fat as a fat cell. Once the amino acids are converted to fats or sugar they follow the same pathways as a fat or sugar, which both can be stored as fat.
This doesn't mean I don't have a high protein intake, because I definitely do. But it is not nearly as high as most, I'd rather focus on sources of protein and timing as opposed to just stuffing down as many grams as possible. I just can't seem to understand the 350-400g of protein a day, I doubt any natural lifter needs that much to grow.