That's the entire point. Anything other than random chance means that someone has "priority". Priority which is typically decided by spending resources. Either time by waiting in queue. Or money by buying at higher than face value from a scalper -- who probably waited in queue, thereby exchanging their time for money.
If the principle being striven for is fair, then most fair to me would be to allow all potential attendees to participate in the sale. If there are more participants than tickets, then the most fair mechanism which does not reward time-rich participants is random lottery, not a queue. A queue rewards those who happen to be available for registration the moment it opens.
Fans don't want a lottery, though. They want to be 100% sure they have a ticket to the show. It's a gratification thing.
Not everything can be 100% optimal and profit maximized. The current ticket sales method works great, if you eliminate the rent-seeking scalpers, through simple regulation.
However, ideally we should also consider it shameful to buy from scalpers. You run a high risk being scammed, they can resell the same ticket multiple times, and you have no recourse.
Your original response was that there wasn't a similarity between unpaid internships and concert ticket sales. And now your response is that more optimal systems are less desirable, which is a fine answer. But it's certainly a choice to choose the less-optimal system, with the understanding that that choice is going to lock out some people due to resource constraints. And the current method rewards time-rich people in a very similar way as unpaid internships. They receive access to experiences that others can't "afford".
If the principle being striven for is fair, then most fair to me would be to allow all potential attendees to participate in the sale. If there are more participants than tickets, then the most fair mechanism which does not reward time-rich participants is random lottery, not a queue. A queue rewards those who happen to be available for registration the moment it opens.