Advice on adding user stories to Masters thesis
I don't like including large amounts of "raw" data in a thesis, paper, or any other printed medium, because it does not contribute to the main text, and if you've already summarized the essential data in the thesis, then you don't need to explicitly include the data.

That said, you do want to make the data available in some medium. Perhaps you can make it available as an online repository (perhaps your school allows for "attachments" or "supporting information" to be included with your thesis. You could then scan the surveys (or bundle them up into a single file if they were generated electronically, etc.) and post them somewhere that readers can access.