Is this really how much concert tickets costs these days?

I am a millennial that has never been to a concert as an adult, but I want to bring my wife to the upcoming Oasis concert in Chicago since we both loved them growing up. The price for the cheapest seat is around $400, and a decent seat is around $1000. I am willing to pay $2000 for us to have a great experience, since it would be a special occasion, but I am just very surprised how expensive it is. Am I getting these prices because I am buying someone else ticket that they are reselling for a much higher price or is this just what you guys pay to go to concerts these days? I would like to know if I am making a mistake buying these tickets or if this is the norm.