Does it matter how long I stay at the strip club with a friend?

Solution 1:

It only matters that you actually went in. Unlike other activities in GTA IV, there is nothing at a strip club that you and a friend engage in together to increase the like %. Such as, when you go bowling, you have to bowl. If you go throw darts you have to actually throw a round of darts. etc.

Getting a lap dance is an available activity at a strip club, but according to the GTA4 wiki:

Visit a strip club. There are The Triangle Club in Northern Gardens (Bohan), and Honkers Gentlemen's Club in Tudor (Alderney). Lapdances are available in strip clubs but are not mandatory in order to complete the visit.

So, next time Roman calls you up to see some "Big American Tee-Tees" you can just humor him quickly and leave.