If they could only make the email address optional, then I'd consider... there really is no good reason whatsoever to require an email address here for someone who isn't asking for a reward.
I have no idea if they plan to do this, but I suspect they might (otherwise why would they require an email address?) and the onus on them to prove they don't intend to do that. Claiming you want to do something good doesn't automatically win everyone's trust.