"loosing" is still incorrect.

In a sense, bookies could be interpreted as "money pumping" the public as a whole. But somehow, it turns out that any single individual will rarely be stupid enough to take both sides of the same bet from the same bookie, in spite of the fact that they're apparently irrational enough to be gambling in the first place.

Suggest making the link explicit with something like this: "in spite of the fact that they're apparently irrational enough to be part of that public in the first place."