2009 Volvo V50 starting car after not driving it for over 7

2009 Volvo V50

I've been leasing the above car since 9/09. Generally I drive it about 3 times a week, approx. Miles a week. After being out of
town for 2 1/2 weeks 7/10, my car wouldn't start. Volvo dealer/leasing site in Charleston, SC told me that this model
had a computer in it which began to drain the battery if car
is not driven for a week or longer. I was able to start the car
with jumper cables, but I cannot believe this is true! Please tell me
if this is accurate.
What an inconvenience! Is there no way to correct this? I have a 3 year lease; do you think I have grounds to discontinue the lease?

Thank you.
Kathryn Symington