Is it legal to withhold overtime pay?

My husband just started a new job last month. he works 10 hours a day, sometimes more, never less. and he works 5 days a week. so he's averaging 50-55 hours per week. his paychecks are only for 40 hours. his boss's wife handles the payroll and each week there is a sticky note with the overtime hours on it. his first paycheck said "10 overtime hours banked" he is now up to about 30 hours of overtime. here's the problem: the only way he can get his overtime is if he needs to go shopping to buy something for our house, car, etc. they won't just cut him a check for his money. also, his boss says whatever he wants to buy, he will order for him (he can get most stuff at a discount due to the type of business) but wants our receipt so he can use OUR purchases as HIS tax write off. so not only is he getting his tax write offs for his payroll (and i believe overtime pay is also a write off) he is getting a DOUBLE write off by using the stuff WE bought for OUR house. i know this isn't right. i have told my husband many times to either quit working the over time and only work his 40 hours, or reuest that they give him his overtime. he's just lazy and won't doesn't like confrontation so he won't open his mouth. he's afraid to get fired if he does. so what can i do? i was thinking about reporting them to the labor & industry board, but not sure what to do from there... can anyone give me any advice? we need that money to pay bills and the mortgage