Seconded. NH do rinse you on fees, sure, but if that gets you all riled up then do head off to a pool (1-2%) fee, then setup an online wallet, then convert your alt to BTC (-TX fees) just like nicehash pays you in, and then transfer it to a hardware wallet (-TX fees) see how much better off you are.
When you factor in "pool" AND "exchange" fees, and the transaction fees, you quickly find that Nicehash fees aren't as bad as you first think they are.
Yep, by my calculations mining most altcoins on traditional pools needs to pay on average ~8% higher then Nicehash for it to be at the break even point. Factoring in the personal convenience aspect of being paid directly in BTC isn't even part of that equation. Obviously if you want to mine for long term holding rather then to pay your monthly bills it's a different story.
It's harder to factor in how much you use due to Nicehash switching your hashrate around a lot (and the very short-term losses from that factor).
They definitely don't have an 8% overall advantage - I'm more inclined to figure that after all costs are taken into account they're lucky if they are even, unless you're running Windows and using their profit-switching software (which make up in part for switching you to more profitable algorithms by costing you MORE outage time in the switching).