Those stats are fake dude.Just so you know,we are talking about bitcoin gambling here which is illegal in most of the countries mentioned in you list.The countries contributing to bitcoin gambling scene are Indonesia/Phillipines along with other European countries.I could be wrong but stats do say lot of third world countries do gamble with bitcoin online.
Ive been wondering too why some of those countries are being listed knowing that some of them do really prohibit gambling which i do really have doubts being listed on their on the particular site that have been mentioned. Those are totally fake stats for sure which it do only emphasize only on some countries without including on the true gamblers online. which is most on eastern.