This has been bothering me for quite a long time and its very unusual for me at least.
So my friend has a WiFi connection (in theory 512 kbps )
When we try to download from browser from PC or Mobile(browser) speed is normal i e 70 - 80 kbps max.
But in Google Play Store speeds are ridiculously high. We tried from his Micromax and my Moto G too.
For example yesterday i downloaded Pocket Tanks (40 mb) in just few seconds. Updates are super fast too.
Even my 2 Mbps WiFi doesn't go so fast.
Its a good thing but I am trying to figure out why not on PC or Browser but only in Play Store?