This isn't some "cell phone tax" that companies are charged for owning cell phones. When you buy any equipment to run a business, and that equipment is expected to last more than a year, you have to depreciate it. There's a particular part of the depreciation schedule that you have to fill in for various pieces of technology, like cell phones, where you have to provide a percentage of usage that is personal rather than business. And you're only able to depreciate business use of the phone over a 5 year period.
What the IRS is saying is that the effort to calculate this percentage with itemized statements, and identifying every person called, is usually greater than the extra few dollars of tax they may collect. Contrary to popular belief, the IRS doesn't want your money, Congress does. The IRS is just making sure you've paid the right amount. If you want to be upset at someone for taking your money, be upset at your representatives in the Capital.
Food for thought, if the phone is destroyed or trashed before 5 years are up, I've yet to find a place in the tax code where you can write off the remaining value, and you're no longer allowed to depreciate a destroyed item. Another thought, if you start a company that earns $500k in its first year, but requires $400k in equipment, if depreciation lets you write off $100k, you'll be taxed on $300k of income that first year, or about $100k, the entire amount of profit for that year. The depreciation portion of the tax code is pretty messed up. And what the IRS gives back in business write offs, local governments take away in business taxes based on how much equipment your business has. For everyone that's against business people and their write offs, try running a business yourself before knocking it next time.