I would call it a "dual-function shop", a "multi-purpose shop" or even just a "kids/dogs shop"!
It could be described as a "combination kids' cafe and pet shop", but I don't think you can simply shorten that to "combination shop". Usually when a shop sells/provides 2 similar or unrelated items or services, those services are mentioned when describing the shop.
"I'm going to the kitchen/bathroom furniture shop."
"He's popping down to the little food and alcohol shop on the corner."