I just logged on twice and now its at 130mbs
Now I'm not saying there wasn;t/isn't a data drain issue...but bear with me

If this happening while sitting in the same spot with good coverage then its an issue, if this is happening while you move between cell towers it's really not that much data - if the game is constantly trying to connect to a server then it's going to chew data, also, if your switching between GSM, 3G, 4G constantly due to poor cell reception or the network is overloaded, then same issue.

Most people don't bat an eyelid chewing through 200GB on the home PC, but 100MB on a phone...OMFG! the world is imploding!!!! Mobile games chew just as much data as WoW, EVE, any online game....it's an online game!

Yes the volume of data has gone up recently with no explanation as to why, but Gree said they were working on it, so knowing the game chews more data, and knowing you have a crappy data plan on your device, just play the game less or stop altogether until it's fixed. When you have a gallon of fuel in your car, you don't try and get 100miles out of it - you either fill it up, or wait until you can afford too.

first world problems or what ?!? Get a decent plan - honestly, I wouldn't even have noticed if it wasn't for the complaints...but now you made me look - 92.68MB in the last 4 days...so what problem? Try closing the game instead of pushing it to the back ground, only takes 30 secs to reopen. Think how much data you will save.