In Germany, the average Software Dev salary is about 50k€/year. That's a total payroll cost of about 60k€/year after taxes, social security etc., so around 300€/workday. Add some money for office space, equipment, overhead, etc, and adjust by factor of two in either direction depending on location and role.
Of course if you hire a freelancer, prices are very different and 1500€/day is very reasonable.
Either I have been very, very lucky or you are basing yourself in outdated reports. In Berlin (one of lowest cost-of-living German cities) you will have trouble to find even junior developers working for 50k€/year.
Of course if you hire a freelancer, prices are very different and 1500€/day is very reasonable.