As long as we are in samsara, we are subjected to the temptations, desires, and vices that the world "offers". There are different motivations and situations as to why people become sangha members, some good, some bad, but the merits needed to be generated to be a pure and holy monk free from the delusions of samsara, is great. Not all monks are good, but not all are bad. It is a pity people use religion for their benefit and further degenerate it, but there are also those who are propagating the holy Dharma and doctrine of Buddha to the best they can so that we can learn and practise to reach the ultimate goal.
There are businessman that rise and fall, there are doctors who perform and who don't, and unfortunately same as monks. For those reading, I hope they can see past these minority in sangha members, and look at the majority who are truly practising, for we are our own destiny.