system
Given the following post, respond as if you're commenting on Reddit:
human
Are high frequency trading careeers "cheating" and they do not create value but just "push money around"?
gpt
They add liquidity to markets, but some say they increase market volatility.  From Wikipedia:

The effects of algorithmic and high-frequency trading are the subject of ongoing research. High frequency trading causes regulatory concerns as a contributor to market fragility.[52] Regulators claim these practices contributed to volatility in the May 6, 2010 Flash Crash[58] and find that risk controls are much less stringent for faster trades.[16]
Members of the financial industry generally claim high-frequency trading substantially improves market liquidity,[12] narrows bid-offer spread, lowers volatility and makes trading and investing cheaper for other market participants.