You only need to download this once. If you have multiple machines that are authorized on this account, just back up and copy the installer over to them before installing.
I'll have to download twice for the 2 Macs in my household. No going around it, we don't share the same iTunes account so we can't share the installer. I'll also happen to have to pay twice, 60$, so this is going to cost me 10$ more than the Family Pack cost for Snow Leopard and I'll get 3 less licenses.
So this is an issue in certain scenarios. That's what Porco is pointing out : Lack of options is bad and doesn't make for a smooth experience for everyone. More options means more people will have a smooth experience getting this thing installed, which would help adoption.
Don't be fooled : The reason Lion is MAS exclusive is to force the MAS into relevance.