I have been thinking the same.
What happens once the mining does not pay for itself? Then people will stop mining and the network get insecure?
Unless some big companies have invested in the money and gives it power only to keep it safe?
Due to bitcoin's software architecture does deperess miners by exponential manner, by design, total number of miners are reaching the saturation point these days. At this point, only electricity pilferers & large corporations will survive.
Even now, miners should group in mining pools, because individual miner with typical hardware should wait for block generation & 50 BTC reward some months, due to probability manner of mining.
Relationship & communication protocol between pools and individual miners are not formalized and guarantied, that miner will receive his profit. Pool admins, being FEW anonymous persons, have TOTAL control on mining, even today.
Mining pools are the same large goverment corporations, bitcoin system 'fights' against, esxcepting they are completely illegal & unguarantied.