Salery expectation and reality

Whenever I attended a job interview I got, of course, the question concerning the salery. Here in Germany we are used to get the salery monthly, which means you are asked for your monthly expactation.
Being 26 and having 3years of experience in differnt practices I expect a salery from about 2000€ (which is about 11,50€ per hour).
Here are some examples of what I got to hear in several job interviews:

- Calculating the payment
I was told they would pay e.g. 12€ /hour. Being quite astonished I calculated: that would be 2057€ per months. The employer would write 1920€ in the contract. That is 12€/hour as well - but based on 48 weeks in a year! Their way of calculating the payment is quite differnt from mine. Most employers calculate in the following way: 40hrs/week and 12€/hour => 40hrs x 4weeks x 12€ = 1920€/month
Isn't that great?!

- vacation days
24 have to be given by law (5 working days/ week), some employers grant 26. When working part time it's usually the same. I got a part time contract, which was saying I woul dwork 20hrs/week and get 20days leave. However, what was not written down: that was based on a 4day - week!

- side jobs
when being in a job interview (for a part time job as PT) I usually ask for the possibility to have a side job. It is so kind if the employer consent to a side job (without limitation) and when reading the contract you get to know you would be allowed to earn not more than 400€ in a side job...

The best thing I have heard was the following:

For a job as physiotherapists in a practise, located 35km away from my home, where I would have to drive home visits with my own car as well, I would be payed a basic salery from 1250€ !!!
That is equivalent to 7,29€/hour! At the end of the month I yould earn maybe 1500€ as one gets a proportional interest in the prescriptions you finish in that very month. That, of course, would increase your hourly payment - to about 8,75€. As I write this - that is just an estimate. The employer couldn't say for sure how much the interest would be...

To be honest: If I can't get a job where I earn more than 7,29€ per hour, I will apply at McDonal's or Burger King. Those companies pay about 7€ per hour and I wouln't have to worry about old lady's aching knees or about broken backs and if I might harm the people with my treetments.
I had not paid a lot of money and efforts for my education to end up in a job where I earn as much as a 'burger turner'...