Try this
Code:
on *:text:Bartender*:#:{
  if (cola isin $1-) || (7-up isin $1-) || (RootBeer isin $1-) || (wine isin $1-) {
    drinks $chan $v1 $2-
  }
}
alias drinks {
  var %nicknum = $nick($1,0), %nick1 = 1
  while (%nicknum >= %nick1) {
    if ($nick($1,%nick1) isin $3-) {
      var %nicklijst = $addtok(%nicklijst,$nick($chan,%nick1),32)
    }
    inc %nick1
  }
  var %file = $iif((I isin $3-) || (me isin $3-) || (myself isin $3-),ik,$iif(%nicklijst,ijst))
  $read($+(bar\,$2,%file,.txt),t)
}


NOTE: needs files named appropriately for the different drinks.