I think keeping it in comments here is better since spreadsheets tend to to have a lot of messed up data (looking at previous surveys). What people share is definitely free-form, so I'd prefer to leave the data rather unstructured.
Creating a throwaway is also really easy and bogus comments are easier to deal with than someone messing with the spreadsheet.
However, I've created a spreadsheet (https://docs.google.com/spreadsheets/d/1MAIX9UEnpq0pAsMWr1NW...) if anyone prefers that.