And why exactly wouldn't they charge more and do this crap? That's even more money.

The prices in Germany are already outrageous compared to other countries in Europe. I got a good deal and pay 30 Euro for unlimited data but I've recently checked for a friend and unlimited data would cost her about 70 Euro a month, which is ridiculous.

Yeah I pay 65 Euros a month for an unlimited mobile data plan with Deutsche Telekom, and that's with a young person discount and without a phone included.

If a company could charge you more for something then they are already doing it. Companies don’t ask themselves “what’s a fair price for x”, instead they wonder “how can we get more money out of our existing customers”.

Sadly, this is irrelevant. Running a corporation within a capitalist system will always optimize for maximum value extraction. Even if they can charge more in base price, this scheme always yields even more on top.