Depends if you buy in advance online or direct at the venue.
If online first, you get a barcode to scan upon arrival at the venue, exchanged for drink tickets - works like a club ticket you can print or show on your phone. If you buy at the club, you get tickets. It's the ticket you exchange at the bar, not the barcode.
In what way? Don’t they like drink tickets? Can we use them upstairs on the VIP balcony?
lastly: one rule hasn't changed: giving a bit of tip with your first order at the bar (2€ or so) will get you a much smoother service all night long. just stick to the same person when ordering. I almost always leave a bit of tip, not much, and over the night it's probably a tenner or less, but it makes a difference both for you and them.
This is why I don't go out, all I want is a pint bad enough trying to find the bar now I have to remember the bloody barman and what bar. ?Agree 100%. Especially when in a club like Pacha. Don't go to the main bars on the dancefloor, go to one of the less busy ones, choose your bar staff wisely, tip early, go back to them, and the measures get more and more and the tip pays for itself. And smile!