Because congress said it isn’t.

Everyone has accesss to last week’s data. They release it on their site once the games actually start.

What is wrong with gambling?

People are already doing that. And they’re already doing it with the stock market. And legalized sports gambling in Vegas. And online poker. And pretty much any other instance where people think they might be able to. If this concerns you so much there are much bigger issues to deal with then daily fantasy.

Except that there is no proof that they are the only people winning?

Being consistently good at daily fantasy absolutely takes more skill than season long. The reason inside information can be so valuable in daily is exactly because it is based more on skill than luck. Season long is heavily luck based with things like injuries and waiver wire priority having a huge effect on leagues.

It’s not up to the DOJ, congress has explicitly made fantasy sports exempt from gambling regulations. And it’s a game of skill in exactly the same reason poker is, some people are better at it than others.

In the big tournaments, it doesn’t really help you to pick players who do well if everyone else also picked them. You need to pick players that do well and that other people have picked in large numbers. This could give them part of the equation, but it definitely doesn’t guarantee them a win.

Casinos actually take the integrity of their games insanely seriously because they know if they don’t they will lose customers. If daily fantasy sites don’t someone will and they’ll put them out of business in the process.

So lets ban it, that will surely put an end to sports gambling!

Because they’re so much worse than endless commercials for boner pills?

The only way they are disappearing is if congress makes it illegal or legalizes traditional sports gambling. There is absolutely a market and it completely in the interest of some companies to run a fair game. When they’re taking 10% of every dollar spent on their site there’s no reason to cheat.