Pairs in coffee shops

[seele]

I hate wasting time in clubs or wandering on the streets, trying to meet a girl. This is why I would like to focus entirely on coffee shops, where I can sit down with my laptop and work, read or study, and approach when some nice girl appears. However, they very rarely come alone and when they come with other girls I find it:
1) much harder to approach
2) don't really have an idea how to to lead the conversation, when there is another girl around.

Long time ago when I approached on the street and there were two or more girls, I would simply say that I want to step away with the girl to talk in private and that would usually work. Here it seems awkward to leave girls friend alone in the coffee shop.

Do you have some experiences with approaching in a coffee shop and what do you suggest?