I didn't know it came with a non-skull plate, but to answer your, erm, question, I think a skull on the desk is not really an option for an office which clients would visit.
How is that not self evident? Are hospitals supposed to just populate their facilities with skull enclosures? How about a funeral home? The receptionist is supposed to put a skull on the desk and think nothing of it?
If you're having trouble understanding why someone may take issue with skull cased computers you should look at your own development; it's not progressing properly.
(Yes I know Intel supplied a non-skull cover; you're missing the point as well.)
Is the parent working on a hospital or a funeral home or some such place? Did they mention they are interested in using it in a professional setting? And even in such a setting, does it say anywhere that the computer has to be in prominent display? And is the presence of a skull decoration such big of a deal, when tons of stuff people buy, wear and sport have prominent skulls and similar motifs?
(Not to mention that hospitals feature skulls all around their premises, from signs outside the x-ray department -"danger radiation"-, to labels on chemical bottles, bins where they throw hazardous material in, etc. Heck, anatomical skeletons are quite common in hospitals / doctor offices as well.
>If you're having trouble understanding why someone may take issue with skull cased computers you should look at your own development; it's not progressing properly.
If you're having trouble not insulting people you don't know about their "development (...) not progressing properly" (sic) because of a question for something which many people/cultures in the world would find totally inconsequential if they saw it in an office ("it's a PC with some decoration, nothing to see here"), maybe you should check your manners?