English Has Too Many Stupid, Unnecessary Words

I think my vocabulary is fairly broad, but I often encounter words that are truly unnecessary—is the English language so concerned about syllabic efficiency that we can't just use a few extra words to convey the same meaning?

Here are some examples:

skulduggery
sounds like: a place where one digs up skulls.
actually means: dishonorable proceedings; mean dishonesty or trickery.

tatterdemalion
sounds like: WTF?
actually means: a person dressed in tattered clothing.

cupidity
sounds like: the state of being Cupid, like stupidity is the state of being stupid.
actually means: eager or excessive desire, especially for wealth; greed; avarice.

defenestrate
sounds like: although my knowledge of other languages clues me in, it still makes me think of defecate.
actually means: to throw out of a window.

crapulous
sounds like: a slang version of fabulous, but perhaps meaning the opposite: crappy.
actually means: sick from, or marked by, excessive drinking.

I'm not in favor of pleonasm (the use of more words than are necessary to express an idea), but many English seldom-used/understood words are just a load of fustian (pompous or pretentious language; see also bullshit).