Honestly, it's not so much of a trick, but that the form is a dark pattern.
IMHO, they probably really, really want to require email addresses to register, but are trying to avoid the backlash from power users (aka their content source) that would happen if there wasn't a workaround. Every time someone gets ticked off about this, there's probably a comment within 5 minutes with instructions, and all outrage energy drains away.
@grumple pointed out that throwaway accounts that can't be easily linked to the poster are essential to some reddit communities, which may play a part in why this feature is still available.
Makes me wonder, why do they keep the functionality? Did they forget about the page?
Is this a joke? Participation is assumed to be only on the basis of anonymity. If the baker requested your name, there would be something very wrong around your parts.
Intrusive requests would mean refusal of participation.
It is not intrusive only if you can give a random address. It would be intrusive if all you had available was an address already used for other services. It is intrusive to ask you for, or coming to know, your name.
And there is also a signup button, didn't have to go for any special page