DirecTV streaming issues.

I don't know of any ISP that will provide static IPs for free anymore.  Some only provide them on business accounts (generally much more expensive), others will provide them on a consumer account with a (normally non-trivial) additional cost.  For example, last I heard, AT&T offers them in blocks (how many addresses you get), with the minimum being 5 useful static addresses for an additional $15/month plus a $100 install fee.  I don't consider that a reasonable additional cost to have the DTV Stream service work properly.  Note that many ISPs don't have the problem even with dynamic IP addresses - my "dynamic" IP address hasn't changed for at least 3 years now.  But in many places you have little practical choice of ISP, so you are stuck with whatever tech and policies that ISP uses.

Basically, the problem is that DTV Stream (well, AT&T TV originally) wanted to offer "unlimited" streams to the subscriber's home (whether to satisfy the expectations of customers moving from cable or satellite or just as a marketing edge is unclear) without having that readily exploitable for account sharing.  Unfortunately, there is no really good way (with standard commodity streaming devices) to confirm whether a device is at the home or not.  That would require reliable (and high precision) location capability, which basically means GPS (which streamers, including their own, don't have) - and even GPS often doesn't work reliably indoors, especially in large buildings. 

In the earlier days, they tried using IP geolocation (for other reasons), and that worked OK for some and failed badly for others (largely depending on the ISP used and the ISP's population density in an area), and even when it "worked", it wasn't accurate enough for this purpose.  So now they try using the external IP address, which for (most) ISP technologies successfully will identify streaming devices on the same home LAN.  But it depends on the ISP using a very static address allocation scheme (even with dynamic addresses).  Some ISPs can do that - they have a large enough address pool to rarely if ever need to reassign active addresses.  Others need (or choose) to use NAT'ing schemes that don't have that property. 

Since the customer has no control over how the ISP handles this (and certainly DTV has no control over it), it makes this mechanism a pretty poor choice for reliably identifying the home network - hence their (unacceptable to me) suggestion to get a static IP address.  Unfortunately, it doesn't appear that there is a better mechanism readily available, assuming they want to support existing streamers (which can't reliably report a location) and still have their "as many streams as you want at home" model.  If they said "max 6 streams" or "you can have more at $5 each" or whatever, they could probably do away with the "home" concept and avoid the problem (at least if they dropped streams quickly).  But they apparently don't want to do that.  So some subset of their (potential) customers will not work properly, if they use more than 2 or maybe 3 streams.

Using IPv6 would probably let this approach actually work (since NAT wouldn't be needed and addresses should be effectively static, or at least within a static subnet).  Unfortunately, IPv6 support isn't quite ubiquitous enough right now to depend on for this.  Most streaming devices support IPv6, but not all do - I believe Roku still doesn't.  Most moderate or better consumer routers, gateways, etc. do, but I'm sure not all do, at least adequately.  And the same is likely true of ISPs.  DTV Stream could try to (preferentially) use IPv6 - in fact they might right now - but because of those issues, it wouldn't always work, and when it didn't (so falling back to IPv4) the problem would remain.

[That got much longer than I planned...]