The problem is that while it's easy as an expert to distinguish usage using context, it can make things needlessly hard on students who are learning new concepts, because whenever they're faced with something they don't understand they have to worry about whether they don't understand the concept or whether they don't understand the terminology. For example, sin^2(x) is often used as a shorthand for sin(x)^2 when really it should mean sin(sin(x)). Or in basic combinatorics, n and k and s can mean pretty much whatever the author wants it to mean, which is a pity when you could just standardize on something.