You can perfectly fine divide the block device into a bit smaller chunks so that you can fit a MAC or similar at the end.
With 4k native drives, this became completely impractical. To keep ratios similar, you would have to present 32k byte devices up the stack, which filesystems have troubles with. Or have 1 MAC sector per data sector or similar, cutting your storage in half.
Here's a short thread about the problems with adding it to dm-crypt: http://comments.gmane.org/gmane.linux.kernel.device-mapper.d...
I'm sure you can find more threads if you look around.