Being on the other side of the trade to abit/saturday/sunday I managed to pick up some good arbitrage opportunities. When I converted most of my Steem Dollars to Steem it was those guys on the other side of the trade, I managed to get favorable prices.
As far as I can see as a trader, I'm not used to trading such a huge spread and 20k of steem going back and forth will put most people off. This number will only increase until these bots are clipping 100k of steem and the barriers are completely closed to entry from other traders.
A monopoly 'liquidity' provider will not tighten the spread, something needs to change with regard to the structure of the liquidity game.