I do this quite often when no friends or clan mates are on. While it isn't as hard as real players, it is nice not having to worry about some green guy shooting me in the back to steal my care packages. And if you set the bot difficulty to max, you will get better practice. They dont miss when your sighted. Plus you get access to all weapons, attachments, scorestreaks, etc.For fun set the difficulty to easy and play with the scorestreaks
I'll play bots in Custom Games and set them to Hardened or Veteran and let me tell ya, there are times I curse them because of the sniper shots they get. Since I reached Master Prestige, I find playing against bots more entertaining since whenever I play objective games with real random players, most of them run into corners and pad their precious k/d ratio. I play the objective and don't care if I go negative for as long as I cap the domination flag and defend it etc etc.