Attendees Feedback:
One of the attendees called kumparak also attended the event and described it by following feedback:
Tapping a monster to catch it would result in nothing but an error screen - a particular punch in the gut to many a player who traveled far in hopes of completing their Pokedex, as the park was set to spawn some of the game’s rarest monsters. You’d tap an Unown or a Heracross (usually only available in very specific regions, and certainly not in the middle of Chicago), and the game would crash.
The cost of the tickets was $25, including the fees. Whereas, a lot of them had come travelling from outside the Chicago. But most of those attendees felt that they have wasted their money because the servers were crashing, the cell service was also down and the long lanes while exiting the park.