We just don’t fit neatly into a little box, here’s a link to an amusing bit of memorabilia from 1970’s Nevada wherein boffins try to find the most appropriate industry classification code for brothel workers… 1978: Nevada puzzles over labor classification of brothel workers
And here’s a quick key to some of the other codes mentioned
0291: General farms, primarily livestock and animal specialties
7021: Rooming and boarding houses
7033: RV Parks and campsites
5931: Used merchandise stores
5941: Sporting goods stores and bicycle shops
6519: Lessors of real property, n.e.c.
7299: Misc personal services
7941: Professional sports clubs and promoters
7996: Amusement parks
8081: Outpatient care facilities
8399: Social services, n.e.c.
8999: Services, n.e.c.