According to https://www.kraken.com/features/fee-schedule, that 1.5% is for their instant trade services. If you use the spot trading platform, the fee is lower than that (if I understood it correctly). Most exchanges do this btw, you pay a premium if you use any instant trade services since it doesn't go to the order book, which is probably good for a trade with a huge volume.

You still need to count the withdrawal fee though. Most fiat withdrawal fee is quite "high: btw. Can't be helped since you're dealing with fiat.