Can an active fat person be faster than a inactive skinny person?

I have absolutely terrible stamina because I sit all the time and most of the time. When I walk somewhere I get winded and fatigued really fast. I'm average so I'm not particularly skinny or fat. But I've seen plenty of quite fat people who walk faster than me and do any physical action faster than me. So I suppose active fat person can seriously be in a better physical condition than a skinny or average person who has inactive life?