I have never seen demanding to be a very effective tactic in the DR or anyplace else for that matter. Its good for starting a fight.How does one know what "rich Dominicans do"? Is mimicking the behavior of rich dominicans a good plan? Might be a better plan to mimic the behavior of smart Dominicans.
Demanding is actually a good thing. Many people and businesess get away with nasty practices because not enough people demand and are not persistent. Not that it's easy, but sometimes a person on a higher level will solve your issues. Others, the same person who has caused your issues will "give in", if you are persistent UP TO A POINT to where they are not used to. They are used to people being aggravated, throwing a little rant and leaving.
For example, I know someone who got their electricity bill cut in half. They went and complained, so they sent to guys who performed a check and concluded thah the bill was normal. They went again and demanded to talk someone higher, also said they'd go to "Pro Consumidor". After that the bill was back to normal.
I've also had a few similar experiences myself.
Some posters advise others not to demand because "this is the DR" and you won't change a thing. Yeah, that works on certain things, like not stressing about time, but but complaining and following up on other scenarios could have a positive outcome.
The last thing you wanna be here is a doormat.