Given that Zones can have:
different login identities
different network interfaces
different hostnames
different hardware available to them (disks, adapters, etc.)
be configured to use resource pools thus different amounts of cpu, floating or fixed
Yes, I'd say they are much more useful than chroot.
Reminds me of a recent news story of a guy whose SUV/pickup truck got stuck in cruise control and NOTHING worked, and a cop had to pull in front of him and stop him with his brakes.
And why couldn't that guy just, oh, put it in neutral or turn the key off? Seriously, he said, "I tried the gear shift, the keys, emergency brake. I tried everything and none of it worked." How does none of that work in a 2001 Ford Expedition?
Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (5) All right, who's the wiseguy who stuck this trigraph stuff in here?