Metatrader's memory usage so different on 2 brokers

 
Why is the memory usage is so drastically different on these two brokers?

Same EA and same build (Ver. 4.00 Build 217).

Memory Usage Broker
882,936K Alpari (so much memory used)
17,808K Interbank

Is this normal or a bug?
 
Is same Symbol set in both cases? How many bars in history are available?
 
Yes, of course the same symbol and the same (maximum) bars in history and chart.
 
Installing MT4 in an empty directory solved the problem.