I am not familiar with the term 'gambling exchange', where'd you get it? Many 'sportsbooks' are referred to as 'betting exchanges', but that has become something of a term of art, much like the term 'prediction market'.
In any case, attempting to use a derogatory or denigrating euphemism to refer to something is usually less productive than simply exposing (what you perceive to be) its faults. What specific issues do you have with these markets/exchanges?
In any case, attempting to use a derogatory or denigrating euphemism to refer to something is usually less productive than simply exposing (what you perceive to be) its faults. What specific issues do you have with these markets/exchanges?