Reselling tickets isn't illegal everywhere, nor is that the problem this is meant to address.
Since you've not yet noticed, presently the state of affairs is that for every event being held at a place larger than a double-wide trailer converted into a dive bar online ticket sales are happening, and those online ticket sales are being dominated by bots which exhaust the supply of tickets as fast as technologically possible. Sometimes a little faster because the bots can and will overload the ticket sales sites. The end result being that it doesn't matter where the event you want to go is, or how popular the performer is... You can be sitting at your computer watching the clock and waiting for the time the tickets will go on sale, and at that precise time thousands if not hundreds of thousands of connections will go to the site via bots and they will buy every last ticket. By the time you've even gotten to click the button to confirm that you want a ticket, all the tickets have already been purchased by the bots. Regular patrons simply don't stand a chance anymore.
This law will make it *easy* to prosecute the people who've been ruining everyone's chances of ever seeing a show for a reasonable price.