No, I don't think you're being cruel. I'm assuming from your post that you (or someone else) comes home midday and lets him out for 30 minutes? People who own dogs DO have to work and I would imagine that there are many other dogs that do fine with a routine similar to Roy's.
It's not a permanent situation either. As soon as he's a bit older and trustworthy, you may be able to leave him loose either in the house or in a gated part of the house.
As soon as you feel he's ready, you could experiment with leaving him loose in the house for short periods, maybe 15-30 minutes at first. Then you could leave him uncrated for half of the nine-hour period and see how he does with that.
If you're really concerned about long periods in a crate, you might want to consider setting up an outdoor dog run which would allow him to stretch and move around much more than a crate.
The most important thing to do is make sure he gets lots of exercise and attention when you're home from work.