Several Dunmer are walking around inside the building, wielding glass weapons and touting glass armor, and if you look hard enough, you can find an extremely rare Daedric helmet sitting about, as well. With that said, if you're only really interested in gathering up valuable, rare equipment early on, look no farther than Ghostgate. People of those profession are the most useful to your character, far moreso than plain merchants, who can be found in abundance all across Vvardenfell, usually sporting only shallow, meager coffers and few opportunities.

What is stupid, however, is killing merchants who double as trainers, spellcrafters, spell merchants, or enchanters.

It isn't necessarily true that all shopkeepers have the same mundane set of equipment, and never carry anything worthwhile killing shopkeeps can be profitable, especially if you re-sell their stock back to either Creeper or the Mudcrab Merchant, both of whom make up the only two merchants you should really be using, anyway, if you care at all about getting fair prices for your loot.

Morrowind merchants with most gold