Maybe you imagine that printed transcripts of her speaking engagements were handed out to the audience? Since she was speaking as a private citizen, her notes, drafts, outlines, and any texts would have come from her personal computer or her private office, so you're envisioning a fantasy that someone on her staff is a Bernie mole who would have unlimited access to her IT systems, steal her speeches, risking criminal charges for the theft of Clinton's intellectual property, and face a lawsuit for violating any non disclosure agreements?
Like many public speakers, Hillary often gives extemporaneous talks, in which case there is nothing in writing. Or she only uses a general outline of the key topics she wants to highlight. How is that so important that someone is going to risk their career to leak it?