Whilst I agree with you that there is greater value in a network with an expanding the user base, you are making assumptions to the extent of its growth through circumstantial abstraction and could possibly be existing users moving funds around, creating more wallets, spending through greater merchant adoption, change addresses and tumbling coins.  I feel (not backed by data yes hypocritical of me   ) that alot of people have wised about about reusing adresses and think this will continue to increase as SPV clients are implementing HD wallets for smart phones...