webform event registration - no receipts from contribution page?
To issue civicrm native event participant receipts when using webform civicrm module you must enable receipting for both the Contribution page as well as the Event page (in your CiviCRM) - for all Events; And yes that will be a number of receipts.

If multiple receipts is a problem - you can  use webform native receipting + use CiviRules and custom (last) contribution tokens - to send a transaction rceipt; 

If you’d like to try that - Register for CiviCamp Calgary - it's a form where orgs can sign up 3 participants for up to 4 events/each in on one page;

Added: webform civicrm works with CiviCRM via it's API: from adding donations to memberships and sign up for multiple events all in one form and using sendConfirmation api to send out the native CiviCRM event receipts; CiviCRM gets a little confused we're able to get all that in one payment [natively that's not possible] - reason why I tend to dispatch my own receipts with Rules/Message templates and some custom tokens;