The whole "can't draw a crowd on Sunday" thing flies out the window during the playoffs.
I'd wager it would fly out the window during the regular season, too. Of course, even weekday games sometimes don't sell out. But say it's Jazz vs Lakers on Sunday, February Whatever - we're packing that arena in.
I think initially it might have been done as a concern about attendance. You know, back when the Jazz was struggling to draw at the old Salt Palace.
Just randomly looking at it. In 1984-85 season, the Jazz had multiple Sunday home games (and some in Vegas). The last regular season game at home on Sunday that season was against the Chicago Bulls. Jazz won 110-92 and attendance was just 8,953. The Salt Palace this season sat 12,666. So, roughly 71% capacity. Not good, especially when you're looking at such a small arena (even in the 80s, the Salt Palace was one of the smallest arenas in the NBA).
It looks like Sunday games were dropped shortly after - my guess is when Larry Miller took full control of the franchise.
I know Gail Miller said that they felt it would be very difficult drawing crowds on Sundays, pointing to the playoffs (stating past series hadn't drawn well) but I don't believe that.
In Utah's second-ever playoff game at the Delta Center, against the Clippers during the 1992 season, the Jazz drew 19,911 - a sell out.
Granted, I do believe it's easier to draw Sunday crowds during the playoff, and certainly, a possible sell out might not happen if it's the Timberwolves. But it's not like there aren't times the Jazz failed to sell the arena out during the regular season on weeknight games.
I say bring it back! The No Sunday rule puts the franchise at a disadvantage.