However, when the barrier to entry for providing a service is low you have to be _very_ careful about making that money by negatively impacting the user experience.
If you make money, that's fine. If you make money by taking advantage of users, you can't really be surprised when a competitor pops up and users leave.
Also money is like a drug. What's wrong with taking a little cocaine in the morning and a little heroin in the evening? Nothing, except there are very few people who can sustain that over an extended period of time. You also wouldn't know about them because they neither become very rich nor very famous. ("Hey look there is the most average guy in the whole country who has no exceptional qualities.") The world belongs to the candles who burn from both ends.