Thats very true, however we use "hard" IEM's, ie no battery packs but it does involve an extra cable to a belt pack. For 3 of us with the rack mounted 4 channel headphone amp, leads, belt packs and headphones it came to under £300 total.
I'm sure its the bottom of the IEM quality table but they were still a marked improvement on the rubbish wedges we used to lug around, and would probably be improved again with a headphone upgrade. The ACS moulded ear protectors costs near that for one person so I still maintain its the way to go!
http://www.thomann.de/gb/samson_sphone.htm
http://www.thomann.de/gb/fischer_amps_mini_bodypack_mit_lsregler.htm
http://www.thomann.de/gb/superlux_hd_381.htm