I'm from Germany. If you work for a german company (and by german, I mean a company that usually originated from Germany based on german ideas of social justice), you would get (as an employee - even the lowest level/retail/or similar) a 13th salary, "Christmass money" (anything raging from a full salary to a few hundred Euros) and "vacation money" (same as Christmass money - this goes on top of your paid vacation leave of 25-30 days per year of course).
And if you have a really good company (i.e. most german car manufactures, Siemens and such), you would get a "participation on winnings". This means, that if the company does good, you get a part of the winnings. VW, Audi, Porsche payed around 9000€ per employee in 2014.
Apple gave it's retail employees 0 of those benefits.
Even german equivalents of BestBuy/Radio Shack (here something like Saturn), did give out much better benefits to its employees than Apple ever did.
Apple is underpaying it's retail employees - plain and simple (at least in Germany by german standards).
FYI: I'm not guessing on the benefits - these are 100% real facts. Many of my friends work for Apple in different retail stores across Germany.