Frozen vegetables are blanched, which means flash heated to destroy the enzymes which prolongs shelf life. So you don't get the enzymes like you would in truly raw veggies. But some veggies are easier to eat and digest when blanched/frozen or even fully cooked so there's a trade off.
Try eating frozen organic peas, still frozen and straight from the bag. I eat this a lot in the summer. Quick, cheap, cool, healthy. Also you can add some organic coconut oil on top and it will solidify and taste darn close to ice cream - awesome healthy snack, dairy free. Frozen corn works too but I don't eat corn or grains anymore so I eat lots of frozen peas in the hot summers here.
Raw corn on the cob is good, if you eat corn.
You are right 100% juice does not mean 100% juice - how do they get away with that fraud? The only thing I really read on labels anymore is the ingredients list and even that is filled with lies most of the time.
So yea I'd say frozen for some veggies is still way ahead of the game, but a good bit of enzyme and water rich raw veggies like tomatoes (actually a fruit I think) should be added to the diet also.