Simple, They just want to get an easy way of earning money. Cheating and stealing are part of our human nature. We do have a devil inside of us and we are fond of taking advantage to those people who we know are vulnerable. Scamming has been around in any type of industry, and we can't contaminate those people as they can easily jump from industry to another. Some people tend to scam due to influence of other people, urgency and etc.
yes scammers are doing that, they tell lies and cheat other people. Maybe they are doing it because they are in need of money, but then it is not really acceptable cheating others even poor people are victim of scammers, even it is just small amount of money it is still not correct, if they really need money they should ask help, there are money people who are kind hearted and willing to help. Scammers also do it because of laziness they want to earn money in one click without shedding tears, how terrible they are, their victim work for it and then they will just get it from them like that, lazy person must not exist.