There are no such people with those skills that have a bone to pick with Maria.
Of course he's not happy when it's done, when it was done was when she got treated lower than dirt, nobody but pro-slave people would be happy about that.
Embarrassing people or making them miserable is on a totally different level from ruining their entire life by getting them enslaved. She has a mean streak, but she's not so sadistic that she would go against the entire hotel and start supporting the slave trade.
No, it isn't lazy bullshit, lazy bullshit would be not showing this at all and then suddenly having the MC pissed off for no good reason. No, this is called cause and effect, Maria's treatment led to the MC getting pissed, not to mention a few players, and that will in turn lead to action at some point down the road. For every cause, there is an effect, and this was the cause for which we will be seeing a major effect. Had this gone any differently, it would affect the things to come as well on a large scale. As I said before, Maria going alone and Maria going with the MC are exactly the same, we just don't see it happen if she goes alone, that's the only difference. She still would have gotten enslaved, she still would gotten treated as less than dirt, and the MC would still do exactly as he did before and after. Nothing changes in this case except being able to see it. We also have a third option, keep things as they are, it's much better on screen then off and having her kidnapped changes the target of the MC's rage, that's not what Runey was going for, he was most definitely going for something to trigger the MC raging against the slave trade and its supporters, especially including Cornwall.
There are many factors that all hinged on Maria going to that hospital and getting enslaved in the process, it isn't bullshit, it's the way things are. An effect demands an equivalent level cause and that is exactly what we got. It sounds less like there's actually a problem and more like a personal issue, for which I have one thing to say, not every game is for everyone and not every part of every game is for everyone. If you don't like it, this isn't "Lessons in Love," it isn't like there's going to be a test on what happens in that event later, so you could just skip through it and focus on the parts you do like.