It's Peru, Baby.

Have discovered that a night out in Chiclayo most often involves standing in a gusty street outside a corner shop with one glass and an assorted collection of men, all of whom I am required to kiss upon arrival (yuk). The beer drinking etiquette is:
1) If you want to drink, buy a 600ml bottle of beer (or three for 10 soles - ₤1.70).
2) You will receive a glass, fill this to the level desired.
3) Before drinking, direct a salut (cheers) to the person next to you.
4) They will indicate whether or not they would like to drink, if so, pass them the bottle.
5) Chug your beer, fling the foamy residue onto the ground, pass the glass on.
6) This will be repeated around the circle, until, blessedly, the beer comes around again.
7) There may only be a warm foamy inch left, but if you drink it, you buy the next round.
This way of drinking is extremely sociable, and encourages people not to get unfeasibly intoxicated too early in the evening, as consumption is monitored (if you pour an unfeasibly hefty glass for yourself everyone asks you if it’s your birthday). The down side is that you are in for quite a wait in between glugs if there is a big group. Plus, you’d better hope nobody has oral herpes...