can destroy a business - just ban accounts
How do you expect it to be "destroyed" by banning?
It's simple. If the cost of the account "member" for example $200, and getting banned and flying out with the signature company, they will not get anything - I wonder what they choose?
In fact I doubt that bans indeed disturb them (especially those who actually are engaged in some sort of "business"): sometimes it seems that they register a new bunch of accounts faster then their previous bunch is being banned.
With the introduction of the Merit system, it is problematic to make many new Member's accounts. Because they use hacked accounts 2011-2014 years. And their number is definitely limited!