Why is the exchange rate for cash—> BTC always more expensive than blockchain updates on exchange rates?

I personally prefer using Coin BTMs, but the one drawback is the price difference.For example when I checked earlier, it was 1USD to ~8800BTC but all of the machines in my local city are at about 9500-10k.Why is this?

Submitted January 19, 2020 at 03:46AM