Lots of reasons, but some examples are:
Performance boats are more likely to have flatter bottoms. More rounded bilge cruising oriented boats will have deeper bilges which can accept tankage and equipment and allow much more storage. Long keels are good for offshore cruising but not for performance. The comment above about getting there a couple of hours earlier but doing it less comfortably applies.
I would put Jenneau in the same class as Hunter. A lot for the money but not nearly a Sabre. Did you look at the J42?