Not that I compete, but I've never had any numbers nor step counting. I eyeball a decent distance (which in my gym, is actually out the door because it's not long enough for a runway unless we open the doors and put mats outside xD) and then adjust as I run if I have to. 95% of the time, I can guage a good distance. Although when it comes to other things, like doing a roundoff just before a mat, I'm absolutely awful, I miss half the time!
I can see that in a competition setting, it's important to know that you've got your distance right the first time. It makes sense to have a specific number in that context.