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As mentioned, some clubs scout the casino floor to try to bring people in early, but don't expect that everywhere...tipping works for females also...unless you are a local female, you pay cover in most clubs in VEGAS...many cities allow females in free to attract the guys and build traffic, but this is VEGAS, they have the traffic, so they dont need to do that...a group of girls can still slip past the lines with a smile and small tip to the doorman ($20-$40 for a group of four should do it (still cheaper than the cover and lets you skip the lines)...tipping them is their main source of income, so you help them, they help you..common sense right?...
the earlier the higher the chance of this working..dont expect to show up at PURE at midnight and expect anything other than a long wait...LONG wait, regardless of how many girls there are...
The main complaints i hear among door personnel is that people come to vegas and think the rules in their cities apply here, they dont!...why do girls expect to get in places free? isnt this 2007, where there should be equality? Sure, work the guys and have them pay, I have NO problem with that, just don't expect everyone to be giving when you you refuse to give....its amazing how far politeness and supporting someone with a tip will get you...it's just $20...what is that in the grand scheme of your overall trip costs?... how much did you pay to come to Vegas? chances are you are going to spend at least $1000, so show some generosity to people trying to make a living....(ok, off my soapbox now...but, seriously)