The money making argument is totally flawed - after all a gallbladder only comes out once anyway. Why are gallbladders taken out on the NHS if the only motive is financial? Why do doctors submit to the procedure if it is ineffective? The only logical conclusion is that gallbladder surgery is effective and safe (in the commonsense accepted sense of the word).
If Liver Flushing did work, it would be associated with side-effects like pancreatitis etc. Of course the complication rate is not known - and some of the posters here seem to ignore the problems commented about on here even.