Maybe i misunderstand but 'Fill order' are Free.

Create and cancel cost a fee (spam prevention) - but the fee is fixed price; i think it is very competitive compared to Bittrex/Poloniex ect, which do not charge to place or cancel an order but when you get filled you are paying 0.2% - i.e for every $100 worth of crypto traded you are paying 20 cents.

Limit order create 0.0121 BTS - $0.00164 USD
Limit order cancel 0.0012 BTS - $0.00016 USD

There is a month I was reading an article about why Bitshares is charging a Fill Order fee, is in order to prevent spam and also apis/bots (whales) that have a lot of ressources can pump or dump the prices according to their interests, sorry for my english i feel more comfortable in spanish or french.

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