Burst is decentralized by design and a huge mining operation has significant overhead costs.

Crunch the numbers: More than $ 200 000 in hardware and high power cost every month for running some Petabytes. Today the whole networks mines exactly 1 Mio Burst a day.... so around $ 800 worth of coins.  So he maybe mines $ 200 worth of coins a day... with so many costs.

It's just a matter of time until the network will be over 20 PB and growing. The piece of cake for this big miners will get smaller and smaller.

http://burstcoin.biz/charts/burstcoins-mined-per-day