Google Changed Standard Plans for Using Google Maps .

Google no longer support keyless access (any request that doesn't include an API key). Now You must include API Key in your googleMap API Request .It includes all API Request like GoogleMaps Places , Autopicker , Google Maps Javascript API , Location Picker API .You can't Use Google Maps API without API Key generated for Google Maps . API keys allow us to contact developers when required and help us identify misbehaving implementations.

The new policies will apply immediately to all Maps API implementations created on or after June 22nd, 2016. 

There is one Restriction Came with This Update From Google .

Your Application Using GoogleMaps Can have 25,000 map loads per day free  to new Google Maps ( Updated As Per 22 June ) JavaScript API , Static Maps API, and Street View Image API implementations. 

So For very Large Websites You Need a Premium Plan License In order to Use Google Maps , Places , Google Maps Javascript API etc . 

Google have also reduced the daily map load maximum limit you can purchase for Google Maps JavaScript API, Static Maps API, and Street View Image API from 1,000,000 to 100,000 requests per API.

In order to gofor More Request than Standard Plan you need to go for a Premium Plan license, which includes technical support and a Service Level Agreement

Google now count Google Maps JavaScript API client-side requests towards the daily limit of the associated web service API.

Google Maps Standard Plan Policy Updates Summary

https://developers.google.com/maps/pricing-and-plans/standard-plan-2016-update?utm_source=geoblog&utm_medium=social&utm_campaign=2016-geo-na-website-gmedia-blogs-us-blogPost&utm_content=TBC

Google Announcement For changes to the Google Maps APIs authentication and usage limits:
http://googlegeodevelopers.blogspot.com.au/2016/06/building-for-scale-updates-to-google.html