Brisbane forward Nick Kenny can only dream of the kind of mind-boggling dollars that have lured Bulldog Sonny Bill Williams to rugby union in France.

At 189cm and 103kg, Kenny is similar in size to the 191cm, 105kg powerhouse known simply as SBW.

That, though, is where the similarities start and end.

Their pay packets and profiles are as far apart as Canterbury in Sydney and Toulon, the French club reportedly prepared to pay Williams $3 million to play for them for the next two years.

Kenny has never met Williams and isn't aware of the circumstances behind his decision.

He didn't want to judge the Kiwi star, who recently publicly revealed his disappointment in former Bulldogs teammate Willie Mason's lack of loyalty after he walked out on his club to play for the Sydney Roosters.

Kenny is in the process of negotiating a new deal with the Broncos which will have a few less zeros in it than Williams's current five-year contract with the Bulldogs and the one he's understood to have received from the Toulon rugby club.

Because he's not one of rugby league's highly-paid stars, his opinion on Williams is not as clouded as others might be.

"I don't know too much about the details of what happened and I don't know Sonny Bill personally," said Kenny.

"On the surface, it looks like if you've got a contract and you're walking out on it - that's just not on.

"He's obviously not happy where he is and I don't know why.

"But when you're tied into a contract for a few years and you turn your back on your club and fans you can understand why they'd feel pretty insulted.

"It's not like he wasn't getting pretty well paid."

Kenny said had it been a big-name Broncos player doing the same thing, he was sure his teammates would have been very disappointed not to have been given the news by the player personally.

"You'd at the very least expect an explanation from your teammate as to the reasons why," said Kenny.

"I'm not sure if he gave them one. But if they were all shocked and it was completely unexpected to them, I can understand them feeling pretty let down.

"If you sign a contract and are locked in for a certain number of years, you honour that contract. That's my view."

Brisbane Lions coach and AFL player of the century Leigh Matthews said the moral question with Williams was an easy one.

"The idea is you sign a contract which is a legal and moral obligation between you and the person you sign it with," he said.

"It's got nothing to do with our game because league and union can swap (players) over willy-nilly.

"I don't know the legalities but I wouldn't think you could just walk out."

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