Looking on the internet deeply has found these results:

merch store is the most popular phrase on the web.

merch shop 11,160,000 results on the web	merch store 13,550,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
We just got new merch in my online shop. Jessie:	Now, you said this was a safe place for us to store the merch. She stole all the merch, and then burned down the store. I'll store my merch here.

merch shop

11,160,000 results on the web

merch store

13,550,000 results on the web

More popular!