Who is the "tax community," I wondered.
Apparently, ordinary American taxpayers are not members of the "tax community," since tickets are $500 per person (of which $288 "may be tax-deductible to the fullest extent of the law," according to the event's 501c3 nonprofit sponsor, The Tax Foundation), placing it out of the reach of most American households.
Opportunities with additional perks for the extra generous are available at various levels from bronze ($6,500) through diamond ($40,000). Noteworthy sponsors include soda companies (Coca Cola and Pepsi), a tobacco company (Altria), and alcohol and beer trade groups. Amazon and Walmart as well as other large corporations are also represented, along with H&R Block, Intuit, and various accounting firms.
The website boasts that last year's prom broke all records for the number of Congressional representatives and staff attending. (It is unclear what, if any, price they are asked to pay for their attendance.)
The invitation page states: "Engage with more than 500 of the tax community's most influential executive branch officials, congressional staffers, members of Congress, sponsors, and non-profits. Establish yourself or your organization as a critical voice in the tax reform debate."
The website is here: https://taxprom.com/