99% of the businesses out there cheat on thier taxes, no matter what size company.
But you can only do it in small amounts, overall the money gained is not worth the effort, or the guilty conscience/worry of being caught.
The IRS has oodles and oodles of complicated algorithms that scour your tax data from every which angle, looking for clues to behavior such as this. If they realize you bought more things this year than money you made, it will raise a flag, or if they notice you seem to be living quite comfortably but your mall store reports it can barely pay the rent, they will take notice. If the difference is minimal, you will probably be safe, if its substantial, expect an audit. And if your audited once, you might as well expect one every year for the rest of your life, they will be going over every piece of data on you with a fine tooth comb til the day you die, then probably a few years after as well.