The HI Berlin City West charged me 3 euros on a reward stay. The tax is 5% ...
What tax? VAT? 7%, I think. Or city tax? Normally a fixed fee per room no matter what price.
As I didn't understand the comment, I just made a couple of dummy bookings: normal rate, includes 7% tax, and reward rate, no mention of tax.
City taxes are common in France, Italy, Spain, Germany and some other countries. They are small and can differ from location to location. They are not normally included in room rates. Just have to pay up.
I did see something else, though, that I had not seen before.
*Cancellation policy for hotels in Germany: There will be a deduction from this charge for expenses saved by the hotel (generally 10% of the booking price).
Don't like that.