This rally is certainly being fueled by a lack of supply on exchanges rather than any particularly strong demand/volume on the exchanges. If you were to see this type of depth/volume last year, it would be a joke and you'd know for sure a crash was coming. However the system is different now. It remains to be determined whether this is simply due to us holding or whether its due to large acculumation off-exchange by hedge funds, businesses, and such. With all those bit coin days destroyed one could theorize a huge purchase of XXX,XXX coins occurred by fortress or something which averted an entire bear market worth of coins on exchanges. However, there is no proof and nobody knows for sure. It could all be psychology and a self fulfilling prophecy.