Why do boxers blow so much money?

[DaxxKahn]

But since they are self employed, don't they get to write off certain expenses that helps to lower taxes paid. So any taxes they pay up front gets reimbursed when tax season rolls around.

Nope,once they sign a management contract,somebody is technically the boss,even when their technically a free runner,the taxes are taken out of their purse for the initial income,just like any other employee,the promoter is employing them.
If they were fighting under cards they were the promoter for,then theyd be self employed.

OK then so Haye and ODLH are self employed despite getting paid off the likes of HBO?

Hmmm Lets see

You own a construction company....

You do a job for let's say Wal-Mart

the job is done,
Wal-Mart pays you a check

Are you a Wal-Mart Employee?