Don't be daft. What makes you think Businesses have to treat everyone fairly? If business A wants to do some special deal with business B that gives B special access or the ability to do things that no one else is allowed to, that's just life. It's by no means evil.
Selective enforcement implies a binary decision. This is rarely the case with legal matters: most of the time some discretion is required (even expected) as part of enforcement. This is what judges and juries are for under the common and statutory laws and in interpreting contract obligations.