Crossfit

seems like the workouts are far to diverse to assume you can just say how long you did it and think that this will give you an accurate calorie count for all workouts

They need to add crossfit to the cardio section!

CrossFit is a brand name so I'm not sure if they even can use it.

You can use the calisthentics option. Or create your own.
Calories burned can be widely varied depending on the WOD as well.

They have Zumba Fitness on here

That is actually very new. When I started typing I had actually written that you wouldn't find them or Les Mills and checked to see how to spell callisthenics and saw those listed. I was actually surprised because for the longest time all the entries were generic ones.

I am not certain but it is likely that something had to be okayed along the lines for that to happen. Plus both of those programs provide their own calorie estimations and aren't as widely varied in intensity as CrossFit. Also, those programs are directly aimed at people a lot of the same type of people this site is aimed for, so it is even a marketing benefit for them. CrossFit is a little different in that regard.

seems like the workouts are far to diverse to assume you can just say how long you did it and think that this will give you an accurate calorie count for all workouts

Thats what pedometers are for

Pedometers count steps. They would be pretty useless for determining calories burned in CrossFit.
Even heartrate monitors will not be accurate for CrossFit.