"therefore 123-Reg may have quite a few court cases to fight in 2 years time when they ask their customers for payment."
If they really are automatically signing you up AND autorenewing with a charge then I can't see they have a leg to stand on to enforce it.
However they might well be simply planning to refund on demand and likely will still make bundles from those who don't notice or decide to keep them....
Signing you up free automatically I don't have a major issue with (although opting in would be better), but the auto renewing for something you didn't specifically agree to seems terribly shoddy.
As I understand it, it is also illegal to sign you up in this way under the Consumer Contract Regulations that came into force in 2014...