If you are trying to create a new TurboTax account to start a TurboTax Online return, then yes you will need an email address. If you use an existing account (such as your own), then the actual tax return doesn't require an email address.
Unlike TurboTax Online, TurboTax CD/Download (for Windows) doesn't require an account if you buy a copy from a retailer such as Walmart or Costco. But you must pay for the software, whereas TurboTax Online is free for certain types of returns.
There are also ways of getting a free email account, which your friend could use for other things, like getting a CRA My Account, a Service Canada account etc...
