I got this in the mail as I only used this service once for my first box as it was practically free at the time and then I deactivated my account. The normal subscription is still expensive in my opinion but at 50% off it probably brings it in line with normal groceries.
The conditions say:
This voucher is only valid on one box per household. Only valid on classic, veggie & family boxes for customers with a deactivated account. When using the voucher, you will reactivate your weekly subscription which you can skip, pause or cancel anytime. Cannot be used in conjunction with any other offer.
at 50% off its similar enough compared to woolies/coles.
Its a reasonable deal considering you get to try their recipes and try something new.
Just make sure you will enjoy everything they send you, otherwise you'll quickly lose value.