Re: Bars in santiago
Stand up bars: where you would actually meet and talk to people would be Francifol bar (calle del sol with Gen Lopez st.).
They play dance music: english, merengue, salsa etc. Crowd is young and the girls are just charming. People are always elegantly dressed.
There is a new Bar, just opened in santiago. A must see; if you are looking for an elegant / uptown type atmosphere... is called tribeca. One half is an Italian restaurant and the other half is a bar / dance club.
Pop's bar is a typical local hang-out type place. Its cold and dark inside and there you will see the real local action. Not a very elegant place but you will have fun there on the weekends.
The rest of the places, like the discos, may not be your type of places; reason being: you would have to sit in a table by yourselves and you would not be able to contact any local that way because everyone sits on their own tables and do not mingle with others.
As you have told me that you guys are all single and looking to meet locals, then the places for all to go would be the stand up type bars.
also try to cruise around the monumento (manument) and venture into the streets where you see heavy crowds of people hanging out. there are some exciting places too. Cheap beer and lots of young people.
Remember, santiago folks are a bit different from the people that you would run into in the touristy coastal cities. People is santiago are very friendly and from good families. Just be kind to them and do try to talk to the girls as they are very friendly.