Two examples of why it might be a good idea for the IRS to target anti-tax organizations.

Tim Eyman and Bill Sizemore. Here are some excerpts from their Wikipedia articles:

Tim Eyman (born 22 December 1965)[1] is a conservative political activist in the U.S. state of Washington. He advocates for a smaller state government through lowering state taxes and fees. He has written 19 initiatives and one referendum, 12 of which failed or were voted out, and 5 were deemed unconstitutional, leaving only 4 that were passed by voters and still in effect.
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In February 2002 the Seattle Post-Intelligencer reported that Eyman paid himself $165,000 from campaign donations, while claiming to be working for free.[33] Eyman initially denied receiving payments, but later admitted wrongdoing.[34] The Washington State Public Disclosure Commission, the state equivalent of the Federal Elections Commission charged Eyman with diverting $233,000 from his initiative campaigns. [35] and Eyman eventually settled with the Washington State Attorney General's office, paying $50,000 and accepting a lifetime ban on involvement in any political committee's financial accounts.[36] [37] Since the settlement, Eyman's co-sponsors and chairmen in his Permanent Offense political committee became more actively involved; Monte Benham of Kennewick became the head of Permanent Offense, though Eyman remained involved politically.

Bill Sizemore (born June 2, 1951) is a political activist in Redmond, Oregon, United States.[1] Sizemore has never held elected office, but has nonetheless been a major political figure in Oregon since the 1990s. He is considered one of the main proponents of the Oregon tax revolt, a movement that seeks to reduce taxes in the state. Oregon Taxpayers United, a political action committee he founded in 1993, has advanced numerous ballot initiatives limiting taxation, and has opposed spending initiatives; however, they often propose measures which require a great deal of additional expenditures by the state.[citation needed] Sizemore made an unsuccessful run for Governor of Oregon in 1998. He also announced his intention to run for governor in 2010, but was indicted by the state on charges of tax evasion.[2]
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On November 30 [2010], Sizemore and his wife were indicted by the State of Oregon on charges of tax evasion for failing to file state income tax returns for the years 2006–2008.[2] He had previously acknowledged failing to file in sworn testimony and was indicted after he failed to file during Oregon's tax amnesty ended on November 19. Sizemore called the charges politically inspired and said he had paid $50,000 in estimated taxes for 2006 and 2007. In 2011 he pled guilty to three counts of felony tax evasion for failure to file these state income-tax returns, with a plea agreement to serve 30 days jail and 3 years probation.[16]

Bonus paragraphs:
Eyman sponsored 25 initiatives for 2012, of which only Initiative 1185 made it onto the November general ballot.[52] Approximately 95% of the money to support the initiative is reportedly from "corporate behemoths such as oil companies ... the national beer and soda-pop industries and big pharmaceutical firms."[53]
Sizemore was born in Aberdeen, Washington on June 2, 1951. He graduated from Montesano High School in Montesano, Washington. He earned a Bachelor's degree in theology from Portland Bible College in 1976. After graduating, Sizemore taught bible history and ran a series of businesses.[3]