Is Day Trading unethical?

For those not in the know: Day trading is when you sell a share of a company not long after you buy it, and typically only when it is at a higher (even if only slightly) value than when you bought it.
 
I have heard some people claim that this is unethical because it is stealing money from people, such as company employees.
 
I have heard others claim that it doesn’t force someone to buy your shares, and even increases discoverability surrounding the company’s shares.
 
 
I wanna hear some thoughts, please.