Mayweather is now at 1.2 after having been around 1.17 ever since the fight became official. The odds got higher recently after a few heated updates .
Just as with Trump last year, the media loves to make a fuss about some non-sense 3rd party statements (ie: other fighters opinions on the match, rumours from the camp etc) in order to get more views.
Just as with Trump, everybody talks about it and gets very emotional (ie: lots of non-boxing fans want to see Floyd lose because they think he’s an arrogant dude running scared around the ring).
A month before the fight, 85 percent of the money that had been bet on the winner at William Hill’s sportsbooks was on McGregor .
By mid-July, MGM’s sportsbook had taken close to 1,800 bets on McGregor and less than 50 on Mayweather .
Thus, there are some money to be made if we think logically.
McGregor has an unpredictable style of moving.
Floyd is old.
Floyd does not take the fight seriously.
Floyd is for the first time mentally inferior.
A few perfect punches are enough to end Floyd’s career.
Filtering through all this irrelevant nonsense, one would see all we have here is a match between the best boxer of his generation and the professional boxing debut of a great MMA fighter.
But the fight has to be sold as much more than that. So you need hope and rubbish arguments to talk about.
Is Mayweather winning a safe bet?
Well… what are the chances of him destroying what he has built in 20 years (49-0)?
Probably a bit higher than Romania going bankrupt after 28 years of democracy.
Yet, romanian bonds offer 2.15% yield.
Whereas Floyd offers 20% return of investment.
Is 49-1 worth $300M? 
I don’t know.
But I’ll bet on him. Just for fun.
The thing I’m mostly curious about is how McGregor will dodge the result. No matter the aftermath, how he will continue his career will be a great marketing lesson.
The way he got to this level in just a few years of spotlight is absolutely outstanding.
,  source
 the amount Mayweather is expected to make