This would be an ideal world:
> What if you make the rules so simple that there are NO loopholes and there is no/little possibility for tax avoidance?
Then we could lower tax "rates", reduce dead weight loss, and increase tax receipts.
But no, we've decided, for example, that home ownership is important for everyone so we subsidize home ownership by letting people write off mortgage interest. This has the unintended effect of driving up prices for homes and encouraging people to buy more home than they need.
When taxes are too high, it causes pathological behavior.
Some people will, even if it nets them less after taxes, minimize taxes paid. "Tax shelters" in the 80's would be all but guaranteed to lose money, and yet people would still buy into them because they would reduce their taxes and pay huge fees based on the total taxes that would be reduced. These arrangements were legal (although the IRS was hawkish on them) but actually made no business sense for investors.