Those players with stats full of zeros are not playing scored/ranked rounds. Stats do not show alt, match play and coin room play.
So, a player could be playing for years, in coin rooms only, accumulate the XP to rise in tier and levels, and yet have little to no stats at all.
That is why, IMO, playing coins rooms and showdowns, you cannot judge the competition based on their tier (Tour Pro, Master, etc...).