By making customers download individual apps, your product becomes harder to implement/less profitable for stores which do not have an app with broad customer adoption. That makes you miss out on the long tail, which in this case could be considerable.
The locationally dependent browsing over in store wifi doesn't have this downside. It could leverage exsisting web technology, which makes the development off these apps a lot easier. It might work like this:
1. You walk into the beacon range. The beacon sends you the url: int.somestore.com/locationx?val=123094&locationy?val=594952&locationz=40389 2. It sends you the connection data for the internal wifi which serves up the stores webapplication. 3. The webapp is shown in the estimote app. 4. Profit.