Most TV Dramas, including Hotel Babylon, feature characters from all of the main ethnic groups. Typically, there will also be characters that fit into different groups that are discriminated against e.g. the disabled and people that are homosexual. They do this to try and portray these groups in a certain way with the aim that it will make some people change their views of them for the better. You will notice that a lot of the time they do this by challenging stereotypes and trying to beat stereotypical views of these people. However, through the process of doing this they usually end up using stereotypical characteristics and ideas to create these characters and bring them to life. Technically, they're not really challenging any stereotypes or stereotypical ideas if they are still using them themselves.
The reason why the media uses stereotypes is because it makes it easier to create a character that the audience feel like they know and already know a lot about even if they are a completely new character. This makes the story-telling easier for them as back stories don't need to be covered thoroughly as soon as they are brought into the show, the audience can already connect with them and already have views on them. Also, if a TV Drama or any show didn't use stereotypes or stereotypical ideas in some way it wouldn't be successful. Audiences enjoy stereotypes, it helps them to develop views on certain characters and most of all it I just convenient to them. We have grown up around stereotypes and they are a part of our everyday lives, it is impossible to eliminate them.
Everybody has developed a certain attitude and different views towards different people, these are unique to every one of us but have been shaped by the stereotypes portrayed in the media and our experience. Ultimately, these views won't change unless we are shown something that will completely contradict everything that we have ever though. When we watch shows, particularly TV Dramas where these stereotypes are more prominent, we are looking for what we want to see which links to the view that we have. We don't watch something and look for something that will challenge our views, we look for the complete opposite. We want to see something that will confirm what we think we know about certain groups of people to make us feel like we are right.