Niantic is indeed doing everything it can to keep the huge amount of players they earned when their game launched, and in order to keep the hype going Pokémon GO has added new elements into the game. As per the latest Pokémon GO update, the game introduced Catch Bonuses which makes it so that the achievement badges that the Pokémon trainer gathers will be considered toward what kind of creatures they bump into while out on an adventure. Basically, it means that the more Pokémon’s you catch of a certain type, and the count of your badge total will lead you to catch more of that type of Pokémon. This kind of sounds bad especially for those who had quite enough of Pidgeys, Spearows, and Rattatas, but if you use this new feature to your advantage by getting those badges to the higher tiers you will get bigger catch bonuses and increase your chances of finding rare Pokémon more often.
Pokémon GO now seems to have a lot of grinding involved in the gameplay, and by grinding we mean catching and catching creatures to collect stardust and accumulate achievements for badge bonuses. Now each achievement has three levels, Bronze, Silver and Gold with a +1, +2, +3 catch bonuses toward a rare Pokémon of a particular type. So to analyze that means its 10, 50, 200 of a certain type.
Note that while grinding for catch bonuses is that most Pokémon are dual type, meaning a Pidgey can be both a normal and a flying type creature, which earns points for both achievement badges. At least now players know that after all the grinding, there will be light at the end of the tunnel where a rare Pokémon is waiting for you to throw a Pokeball at it.