Buying ETF vs from Kraken

When I buy $100 BTC from Kraken, it turns instantly to $97. And when I sell it back to cash it then goes to like $95.

Even on + while avoiding fees.

Wouldnt investing in BTC with ETF on vanguard or fidelity have a lower spread or whatever you call that instant trade loss?

I know they’re benefits to having the actual coin, but would rather not have to lose a few percentage points with each trade?

Would appreciate input!