The REI savings are peanuts in comparison to the current corporate welfare system. There is no such thing as tax loopholes, they exist by design. Keep that in mind. No need to sweat it.
REI has benefits, but are exaggerated. For instance, imagine a rental unit $27,500 kitchen renovation that will be depreciated over 27.5 years, $1K per year. Well, your savings are a whopping 14% (this is the typical effective tax bracket for most Americans). Will you feel guilty for $140 savings per year? These "juicy savings" are destroyed by inflation at 2.5% per year (unless is this crazy year). So, your savings over 27.5 years are peanuts. Then, unless you die, you will face recapture tax at 25% flat and this does not account for inflation over your cost basis. Finally, you always have property taxes, maintenance, interest on your loans, etc.
Read NOLO Tax Law & Deductions for Landlords a few times, then you will truly realize that the savings are not as they advertise. The savings are good, but with many limitations. You won't see incredible savings unless you are mega rich.
Finding financial freedom through REI, is likely a fallacy unless your are aiming to lower income. REI is a business. It is still a job. It will consume your time. As you can see through this platform, creating a successful blog, selling tons of books and advertising is more profitable than REI.
You can always volunteer your time for not for profits if that makes you feel better. However, your immediate group of people will benefit the most, Focus on your family, kids, and friends.
Update: read Capital in the Twenty-First Century