When a company spends money to continue its existence, such as rent, it is deducted from its taxable profit. When a person spends money to continue their existence, such as rent, it is not deducted from their taxable income. If people were taxed as corporations the median American would pay no taxes.
Anything not-business-related a corporation spends money on is considered to be a misuse of funds (or fraud).
People are already taxed in similar ways to corporations.