It is probably much higher. If we take a conservative estimate of 10k btc traded per day, on average, and a trade commission of 0.008% (0.004 two ways), we get to $5.6m in little over half a year. Now yes, the have some operational costs etc, but they've been in business for several (?) years.
tldr: back of the envelope calculations show that they must have made more in profit to-date.
For comparison, Bitfinex did 27k in the past 24h. And an average of 22k per day in the past 30 days. So 10k is indeed somewhat conservative. I'd personally guesstimate their annual fees at around $10m, including discounts for larger traders.
What isn't mentioned often is that I suspect they're personally somewhat rich, too. i.e. they were two people into bitcoin in 2010, started the company in 2011. Even if they didn't invest in 2010 which they likely did, in 2011 the price was still in the pennies. A $5k investment then would've been worth $5m today, or $15m just a year ago. Between the two of them, I don't think it's unlikely they've got quite some millions stashed away. And given they've had a $10m investment not too long ago (with a valuation in the tens of millions at least. e.g. Coinbase and Bitpay both have $150m valuations at $30m invested) it's not unlikely they're burning VC money or their own money just to cover these issues and keep an otherwise potentially very valuable (long-term) company afloat.
Mix that with 2 years of not unsubstantial fee collecting and a cheap cost center in Slovenia for the vast majority of their development work, and I think it makes a lot of sense that they can pay this off.
Of course all of this is speculation. The crazy thing is that bitcoin is so young and nascent that we don't even have basic oversight. For all we know the two co-founders could have stolen $5m from their customers, said it was a hack, and continued happily knowing they don't have to work again for the rest of their lives if something happens. Of course this makes no sense seeing as they fronted the loss, but this notion that we are assured by that, rather than say an audit, oversight, blockchain analysis etc, is a reminder of how far bitcoin has to go still.
The trading commission is 0,8% (0,4% two ways), and it is lower the more you have volume. In addition, they have withdrawal fees.
In addition to operational costs probably fraud is also a big cost, but it is very difficult to estimate how big it is for them.
And, they don't exactly need to take it from their profits, they can just do fractional reserve... They are a bank, as are any bitcoin services that hold money for the users.
They are not regulated as a bank, they cant "just do fractional reserve" which you entirely misunderstand. They would be stealing from their customers.
Doesn't just have to be retained earnings from past profitability, it could also be investor cash that would presumably be recuperated with future profitability.
Yup.