Trying to work out what you'd be using these for besides going broke? The house always wins.
Not really. If you can do arbitral gambling then you can beat the odds.
Different bookmakers run different promo for different games.
Usually new accounts will have certain promo that applies to them such as free $100 for $200 deposit.
When we use two different NEW accounts to bet, this would mean a potential gross profit of $200 using $400 capital. These bonus usually requires that you place at least x times of bet. This is to cover the amount of bonus that the house gives out.
Most of these people who uses this model uses bot to scrape the best odds so they can place bet for both direction.
Example. Man U win 0.85 lose 0.95 vs Man City (-1/2 ball) win 0.95 loss 1.00
Account A takes Man U and (eat) 1/2 ball. Win $85 loss: $95
Account B take Man City and (give) 1/2 ball. Win $95 loss: $100
Assuming the player plays both account A and B.
Scene 1: Man United Draw or win: $85 - $100 = ($15)
Scene 2: Man City Win: $95 - $95 = 0
In Scenario 1, player would have a loss of $15
In Scenario 2, player would no losses.
The typical requirement by bookmaker is that the player has to place a min bet of 5-10 times depending upon the bet size.
The law of statistics state that giving ball and eating ball averages will even out the more games that are played.
Assuming you deposited $200 for each new account that gives out $100 bonus.
Total bonus $200
less potential loss from gambling $15 x 5 = ($75)
Potential net profit of $125
Some player go one step further and sign up for an affiliate program that pays on CPA. So they pocket the affiliate commission at the same time. The more accounts created the more money made. But usually affiliate program is not used as they require too much work.