"simon-pure," a hyphenated [adjective] phrase, and "Simon Pure", a [noun] phrase with no hyphen) are [description]s with two [contradictory] meanings, both based on the characters of [Susannah Centlivre]'s [1717] [satirical] [play], "[A Bold Stroke for a Wife]." The description can mean either:

Completely and genuinely [pure]; or
[hypocritical]ly virtuous

The contradiction stems from the plot of the play: a young man (Colonel Fainwell or Feignwell) wants to marry a young woman (Anne Lovely) who has four older [guardian]s: Sir Philip Modelove, an old [dandy] and [ladies' man]; Mr. [Periwinkle], an [antique] collector who doesn't think much of women; Mr. [Trade]love, a [stockbroker]; and Mr. Obadiah [Prim], a hypocritical [Quaker]. Each guardian has different ideas about who would be the perfect [husband] for Anne, and so the Colonel has to do a lot of acting to convince each one that he fits their definition of the perfect man for their charge: he's a [Dutch] [trader] when he talks to the stockbroker; with Sir Philip, Fainwell he's a [French] [gentleman]; with Prim, Fainwell he's an overly honorable and [virtuous] Simon Pure; and with Periwinkle the curious [collector], Fainwell disguises himself as a well-travelled man. However, at the end of the play the real Simon Pure who Fainwell has been impersonating shows up and ruins Fainwell's disguise. "I do affirm that I am the REAL SIMON PURE," he says (Observant Quakers traditionally "[affirm]" things rather than [swear] to them because of the prohibition against swearing oaths in [Matthew 5].)

Thus the "real Simon Pure" is a [true] and [virtuous] man, and the [jewelry] designers, video [production] companies, and such who use the name now (according to a Google search) are probably alluding to that meaning. However, the [false] Simon Pure is obviously (to the audience) a faker, and he's trying to get on the good side of Prim, a supposedly religious man who still asks a girl to "show you a little, little bit of her delicious [bubby]." This is how the undertone of [hypocrisy] became a part of the phrase "simon-pure" for some users, though the use to mean "genuine" is more common.

There seem to be at least four [band]s using the same "Simon Pure" or in one case "The Simon Pure" -- it's not obvious which sense of the phrase they prefer, except maybe for the [South Carolina] [Christian rock] and [Pennsylvania] [Christian metal] bands who have both chosen the name.

The [William Simon Brewery] in [Buffalo, New York], made a [beer] called "Simon Pure"; Simon bought the [brewery] in [1896] and it closed in [1971], though the brand was made at another brewery until [1980]. [Merchandise] with the Simon Pure [logo] seems to be fairly commonly collected, judging by the collectors' sites and auctions found in another Google search.

Sources:
http://wordsmith.org/awad/archives/0404
http://www.bartleby.com/61/66/S0416600.html
http://www.answers.com/simon-pure&r=67
http://www.broadviewpress.com/bvbooks.asp?BookID=45
http://www.bibliomania.com/2/3/174/1112/15825/1/frameset.html
http://www.queensu.ca/drama/jstephenson/DRAM202/test1answers.html
http://myweb.dal.ca/dmcneil/bubble/centlivr.html
http://cinealain.wordpress.com/2007/03/31/randoms-ideas-concerning-susanna-centlivres-a-bold-stroke-for-a-wife-and-john-gays-the-beggars-opera/
http://www.myspace.com/simonpure
http://www.myspace.com/simonpureofficial
http://music.download.com/simonpure/3600-8431_32-100591970.html
http://www.mbus.com/bands/sc.htm
http://www.virb.com/thesimonpure
ttp://www.biniasz.com/buffalosounds/soundsofbuffalobeer.html
http://ah.phpwebhosting.com/h/jablonski/breweries/index.html

Simon-pure (idea)