the reason i hate them is simple. "ignorant f#%ks" think "oh, i can install this on any computer i come across, because how will they know it was me, time to leech free cpu"...
there have been many cases where people have been fired from their jobs in america for doing said infraction. the developers of F@H and BOINC specifically say "install on your own computers only", for a good reason.
taxing a cpu to a constant 100% usage draws extra energy, wears out cpu fans faster, makes rooms louder, and wastes network bandwidth.
if i ever find out who has been doing it at my work, i hope my manager reams them out and sends them the bill for replacing roughly 500 cpu fans, labour for having dell install those fans, and the equivalent year's worth of power consumption for 500 computers.