I do cardio so I can eat more.
Same. I enjoy cardio more than I enjoy hunger, so it's my preferred means of creating a deficit. Plus, when people say: "You can't out-train a bad diet," not so deep down, part of me wants to say: "Watch me."
When I'm at the uni gym, I like to get on the cross-trainer and just go for an absurd amount of time. On Mondays I have three hours between lectures, so after my strength training I'll happily get on the cross-trainer and basically go into a semi-trance for a while. Kills time, is good for the CV system, intensity's at a therapeutic level, and it nukes energy, which means easier fat loss when needed or more food when wanted.
I generally prefer to do cardio right at the upper end of low intensity. Find a nice comfortable pace where I'm still breathing through my nose. Cross-trainer says I burn about 750kcal/hr doing that. IIRC their numbers are based on 70kg males doing it, so for me that's pretty darn close. Assuming a BMR of 1,700kcal/day (which is right about the predictions given
here), I'd burn about 70kcal/hr at rest, so that's still about 680kcal/hr, normally in an hour that would have otherwise been spent trawling facebook anyway. At that intensity, I find it doesn't impact my strength training, either. On the flip side, if I do cardio that mostly uses anaerobic systems, it will very quickly eat into lower body work.