Wrex, every theatre in the UK almost without exception operates at a loss and rely on sponsorship and subsidies to sustain them, but it's generally felt that this is worthwhile to sustain live theatre.
The arena was not intended to cater solely for concerts, it also house conferences and exhibitions as well as theatrical performances which won't fill the 1,200 seat theatre.
Llandudno Youth Music Theatre recently presented the musical The Wiz there, and it was a fantastic production put on by local youngsters aged from 11 to 18. There are also theatre and ballet workshops there on a regular basis.
In November it will host a major national conference, as well as Wales Rally GB, which between them will bring thousands of high spending visitors to the resort.
However i think it would be unrealistic to expect it to host events on a nightly or even weekly basis, even some of the country's major venues don't achieve that.
I think the truth about concerts is that it is too small to take major bands/solo artists which somewhat limits its' appeal. Perhaps you should write to the theatre management to suggest some acts/names you would like to see there?