The advantage that Google has over Amazon is lots of data on local businesses and maps. It knows when they’re open, how much traffic they through searches and, if they’re tracking Android or Google Maps users, how much foot traffic they actually get from customers.
What’s missing is an easy way for these companies to make their services and products available online. One low tech API is to employ task runners located close to these stores to fetch the items. However, this is a very high cost proposition and doesn’t afford Google much margin. What Google may do is employ some type of device or POS tie in that would allow for these stores to receive only payments.
Perhaps the biggest impact of Home’s local shopping can happen in urban centers where the density and number of specialty establishment makes it easier to compete with Amazon Prime Now. In any case, the war between Google and Amazon is heating up.