Congratulations! With vintage stuff, take a deep breath before you buy. I seriously adore vintage, but I tend to wear my "real vintage" stuff on special occasions - often events with fellow vintage aficionados. I have two vintage dresses in my wardrobe that have yet to be worn to an event because I'm so nervous about them. And I have a weakness for vintage gloves, which, again, I don't wear or only wear for five minutes because I'm not used to them.
The "real vintage" stuff I wear most often is - brace yourself - 1970s! Silk dresses and blouses from the period, and shoes, are quirky without being preciously terrifying to wear or "costumey." Plus, I can launder them without trembling in fabric conservation fear.
I also get lots of wearing value out of vintage jewelry.
Everybody loooooooves a vintage hat. You'll get acres of comments if you dare to wear one.
I have rounded out my vintage-for-wearing with some basic vintage accessories - a purse and shoes in brown, and a purse and shoes in black - which draw a lot of attention and compliments, and make even modern clothes feel more vintage overall.
Also, shame on you, snooty steampunk-rock store! It would be better business to greet everyone courteously. You could be gift buying, or coming from signing a contract on a lucrative new job, or planning a major style change.