Why big corporations can get away with this? It comes down to people. Little guy working at tax office doesn't have enough confidence to oppose Apple or Google but will have world of confidence to scrutinize unknown small businesses.
I see companies like this popping up all the time offering services that allow profits to be concealed under some bullshit scheme. It might take a few years before tax authority will catch up but they will eventually find every single client of such company, they will conduct detailed audits and will issue new tax bills with penalties to all involved.
I specifically said, tax authority won't accept tax deductions they don't like. They will simply issue you new tax bill and couldn't care less whether what you are doing is legal or not.
It's up to you to challenge their interpretation of law through legal system if you think what you are doing is legal.
By the way, EU’s executive Commission is currently looking into Ireland and says what Apple is doing could be illegal under EU law. If confirmed, Apple will get a huge repayment bill.
source: http://www.news.com.au/finance/business/is-the-apple-tax-dod...