Why is a Muggle T-Shirt so Hard to Find?

The brains behind Harry Potter World are having a hard time keeping up with souvenir demand. The lines for the new Harry Potter World attractions are long and apparently people have been keeping themselves busy by hitting up the gift shops to buy the latest and greatest wizarding trinket.

Just in case you could not find your favorite wand or house scarf while in the park, Universal is putting together an online store to meet the overwhelming demand for all things Potter.

It's only in the beginning stages, but from what I see I am disappointed in the merchandise selection. Where are the cute "muggle" t-shirts? These items look more like dungeons and dragons meets a heavy metal concert. 

Some sample screenshots are below....

$100 for a robe that they will use as evidence when they find the bodies in your backyard...

 $29.95 for a hat that out of Harry Potter World context makes you look like a homeless scarecrow.

...and finally adult t-shirts that scream "I DON'T/CAN'T TALK TO GIRLS"