Pretty stupid question about latency

I am just curious about this, how come when I being from EU, can play WoW and Runescape on American and Australian servers and have around 100-150 ping but then when I play CS on those servers my ping will be 300+ and unplayable?

 

I'm inexperienced in playing on different servers on CSGO, how does that work? I mean are you sure you're playing on those servers? My only guess is you probably picked the wrong server. An example is US west and US east. For some reason it was made a big deal in a pro match I've watched. I live in the SEA region and I get just under 200 ping on US west but over 300 on US east. Same with RS servers, some are significantly higher even though they're servers in the same country.

I remember Hiko was playing with Hooch. Hooch is from the CIS scene and Hiko from US. Yet somehow Hiko and Hooch were playing in the same team and somehow they were both top fragging. This isn't exactly the answer you're looking form, but it's all I got.