Because he's much weaker than Kami and it's hard to fit. If there were no scouter numbers I'd have it the other way around, but like I said, hard to fit...
I do, but only for the first portion of the series. I've never made numbers past the 23rd TB that aren't scouter numbers as they get incomprehensibly high by the later Freeza arc.
If we assume BOZ Roshi is actually 13.9 like withheldforprivacy then Chaozu would be a lot easier to fit.