Lets stick to the stats, I will restate them again.
NBA
Team Draft Picks FA or Waivers Trade Total
ATL 4 9 2 15
BOS 3 5 7 15
CHA 3 3 9 15
CHI 4 5 4 13
CLE 4 4 7 15
DAL 0 7 8 15
DEN 1 4 10 15
DET 8 5 0 13
GSW 6 5 3 14
HOU 3 2 10 15
IND 5 3 5 13
LAC 4 6 3 13
LAL 6 6 2 14
MEM 4 5 6 15
MIA 2 9 4 15
MIL 6 3 6 15
MIN 5 3 7 15
NJN 2 7 6 15
NOR 0 5 10 15
NYK 3 5 7 15
OKC 7 1 7 15
ORL 4 3 8 15
PHI 8 2 4 14
PHX 2 7 5 14
POR 4 5 6 15
SAC 7 2 5 14
SAN 7 3 3 13
TOR 3 6 6 15
UTH 6 4 3 13
WAS 7 1 7 15
Total 128 137 169 434
So for the NBA only two teams have no draft picks, one has one, three have two, five have three, seven have four, two have five, four have six, four have seven and two have eight.
So for the NBA the range is 8, the median is 4.5, the mode is 4 and the mean is 4.266666666666.
I can't do stats for all the top leagues in BB, but I would specualte it is more like a range of 6, median of 1 mode of 0 and mean of 1.5 based on the two leagues I do know Australia and India and most of those are worthless 3k scrimmage scrubs or players from the dim dark past that are no loner important. How many players have their star as the player they drafted like Chicago, Miami or OKC? (If we had this discussion a season ago we could have added in a ton of extra teams like Cleveland, Charlotte, Denver and Orlando) I will be willing to bet it is very rare.