If an establishment wants to give non-techies the opportunity to attend, yet remain "accessible" to those without piles of money, there are a few solutions.
1. Don't take reservations.
My favourite restaurant operates on this basis. On a Friday or Saturday night you will queue for up to an hour for a table. If you prefer to avoid peak hour, there is rarely any queue for lunch. I've eaten there over 100 times and I still don't begrudge the time spent in the queue.
2. Run a lottery
Popular theatrical productions are great at this. If you don't want to book months ahead (or can't afford to spend hundreds of dollars), Book of Mormon offers a ticket lottery before every show. Just show up at the theatre and enter for your chance to win one of 21 discounted, front-row tickets.
To clarify, I'm not suggesting that the establishment in the OP wants to let the poor and/or technological illiterate to attend. However other places have managed to do so without hurting their brand.