In practice people are convicted of criminal trespass when they have either obviously entered unlawfully or have entered lawfully and have been told to leave and have not done so.

If a property posts a sign or sends a letter that only people wearing green may enter. If we allowed the owner to prosecute people found to be on the premises without the correct color even if they leave immediately upon being asked to we would indeed be letting the property owner enforce their whims within the scope of their property with punishments handed down by official channels.

In practice this is basically impossible in most or probably all jurisdictions although probably untested in virtually all instances. Basically almost nobody would press such a case and if they did the local government would be unlikely to pursue such charges or succeed in them if pursued.

Such matters are inherently local and subject to local laws but lets look at the city of Seattle as an example. In Seattle you can call the cops if people are on your property and wont leave however even in that obvious case prosecution is unlikely unless some other crime is committed in the process. The city pursuing a case against people that merely broke your personal rules for conduct on your premises isn't explicitly mentioned not because it is allowed but because it is beyond the pale of absurdity.

Reading for example the guidance provided by the city of Seattle I read that local businesses partner with law enforcement to remove bad actors according to the contact trespass program.

>The Contract Trespass Program is an agreement among private property owners, businesses and the police department to regulate conditions of entry onto their private property. This can include prohibiting people on the property altogether, or it might involve allowing people onto the property only under certain conditions.

The conditions that can be enforced through the Contract
Trespass Program are listed in the agreements

and posted on the premises. By signing a contract with the police department, property owners agree to let police
officers

warn and then arrest people who continue to violate the conditions

when the owners are not present.

They enumerate the reasons they will cooperate in removing parties and arrest people who have been warned by authorities that they are in violation.

Looking further into the matter businesses don't HAVE to participate in the contact trespass program but they are told that

>Officers may still arrest for violations of SMC 12A.08.040 (Criminal Trespass) on private property regardless of a trespass warning agreement if someone with the authority to set the conditions of entry or revoke the privilege to be on the property has previously warned the individual of the trespass violation and will testify as a witness

They might arrest people who have been previously warned if they are still there when the cops arrive

They are further warned that

>For a successful prosecution, someone with the authority to control the conditions of entry and revoke the privilege to be on the property must testify that the person (1) knew or should have known the conditions of entry, (2) violated the conditions of entry or had their privilege to enter the property revoked, and (3) the person refused to stop the unlawful behavior or leave or they returned to the property after having their privileges revoked. Property owners are encouraged to keep detailed records of the interactions with trespassers on their property.

Please note especially

>the person refused to stop the unlawful behavior or leave or returned to the property after having their privileges revoked

In summary the two situations are exactly alike in the alternate universe in which trespassing is used in that fashion but instead of suggesting a weakness in the defense of such CFAA act cases it suggests that were trespassing laws used in such a fashion they ought to be challenged under the same premise.