Why shouldn’t they have a right to deny Delaware the right to profit on the back of a business NFL owners have developed over several decades?

So the NFL should have a right to decide what people can and cannot do with facts? Does the NFL have a right to deny Delaware from reporting who won a game without paying a royalty? How about who played in the game? Or that a game even happened?

The NFL has rights over the broadcast of it's games, not over the results of them.

I think they do understand, at least in some ways, which is why they seek public-financing deals with host cities, why they're so protective over licensing, etc.

If they were to depend on ticket revenue alone, they would collapse financially.

While the League has legitimate concerns about the impact of betting on the integrity of their game, let’s concede Lesniaks’ point that the NFL is fighting this because they’re incurring risk and expense while getting no commensurate reward.

The implication of conceding this point is that the NFL would be ok with it if they were getting a cut. This is not true. The NFL rightfully fights against gambling on its product to maintain the integrity of its product. Taking any money at all from gambling would lead very quickly to the NFL being nothing more than WWF as there would be pressure to maximize this income stream by tweaking the results ever so slightly. Then it's in for a penny in for a pound.

There is gambling on NFL games, most of it illegal. Fighting against the legal gambling that goes on in Las Vegas would be tilting at windmills, while fighting against the illegal gambling is probably even more so, though the league continues to put up a good fight. I don't deny that the NFL realizes they benefit from the interest created by the illegal and the legal gambling, but there are very good reasons why they can never get in bed with any gaming activity or organization if they want to survive.

they have a right to ensure that their brand is associated with quality products that don’t tarnish said brand.

...Detroit Lions.....

What would be that actual cost to the NFL if gambling on NFL games was allowed in Delaware?
It seems that the only direct effect on the NFL will be marginally increased interest by those gambling.