No need to get something that fancy for short-range use in a conference booth. I have a $40 T-Mobile Wifi hotspot that I activate for $10/GB when I need it.
It came in handy at a conference where the provider's network went down and we could still process credit card orders over the cheap hotspot. Though I imagine that if everyone used them, the cellular networks would not keep up with the demand.
As long as the cellular networks are on top of their game, they shouldn't have a problem. Conference centers can be blanketed in microcells to ensure good coverage even when spaces are extremely crowded and utilization is high. My own (limited) experience is that cellular is more reliable that WiFi in such an environment. Your problem would more likely be accidental interference from other hotspots on the WiFi end.
Conference centers can be blanketed in microcells...
Except the conference centers would charge the carriers millions to install any equipment, so the signal usually has to punch through windowless buildings from the outside.
It came in handy at a conference where the provider's network went down and we could still process credit card orders over the cheap hotspot. Though I imagine that if everyone used them, the cellular networks would not keep up with the demand.