You can now set your own reply email address for EMail Marketing. This is set in the Email Marketing Setup:
When you set this, your emails will look like this to participants:
For advanced users, we still recommend full white labeling. This option is similar to what most email marketing offerings do, but can impact deliverability rates some. This is due to the fact that the email is may not be verified against your website/email domain. For example, when an email is sent from RunSignUp, there are DKIM records that identify it. There is not the same capability in simple white labeling, only in full white labeling.