Bittrex charges a flat rate, regardless of size
when I pull the coins from Bittrex to the pool's wallet, it's done as one tx so we only have to pay the 0.02 once. that is then divided up between all the algo's to be paid that day so it's fair. (ex: if sha and scrypt get paid in one day, they each loose 0.01 from the total before payment is sent out).
Standard Tx Fees apply when the pool sends out payments. it's done as a sendmany (one big tx) to keep fees at a min.
When I send out today's payments i'll post the txid so you guys can see how much fees are costing.