You asked if you would be able to carry at the stadium of fire event. Though by law they cannot stop you from legally carying at the event, they will be doing "security checks." Of this I am sure. However, if they want to consider themselves as a "secure facility," which by definition of the law-they are not-means that should you carry to the event they must provide a secure locker or facility for the storage of your weapon. If they don't do this & refuse you your rights they violate the law & are subject to prosecution/suit.
If the stadium is at the BYU football stadium, other restrictions may apply even though it is a public venue. Perhaps Clark can chime in and be more specific, as I am sure he is more up to date on this than I. If the stadium erfuses your right, they at least, haven't gat the same leg to stand on as the court houses, which have unfortunately been allowed by the legislature to create their own rules concerning carry at their facilities--I certainly hope that this can & will be changed as it allows too much abuse & denies many the right to carry while traveling to & from when they are using public transportation--which we all know is not safe!
I don't know if they will be patting down or wanding folks as they enter. Regardless of whether they have a means of detection signage, storage lockers for guns etc... they are not and cannot pretend to be a "secured area" under the law and could not use such designation to have you charged with carrying of a weapon into a secure area.
Whew, with that being said they fall into a odd little area as far as stadiums go where it is definitely Private property, as opposed to the E-center (public property). Basically it is like this, IF you carry, hide it well, IF they find it, take it to your vehicle, (where it may be stolen) If you are able to get inside with it and it is somehow discovered and they ask you to leave. As long as you are not causing a nuisance or interfering with the venue or scaring others then you have not committed a crime. (Not even trespass) if you refuse to leave, but..... it MAY be better if you did at that point because your option at that point when faced with a trespass charge would be an affirmative defense that you weren't bothering the venue or
You'd have to decide if that was worth it. Here is something to keep under your hat, I am currently penning some legislation to make the above scenario on trespass better for CCW holders. That is all I can say at this point.