Well, any purchases of the My TV Pal will have no connection (financially, at least) to your Dish Network account, so a separate "account" is reasonable. The "account" is probably something they enter into the system that allows all future transactions from the website to go through uninterrupted, as well as indicating for records that as a Dish Network subscriber, you understand that you don't "need" this equipment, but you wish to purchase it anyway. The word "account" is probably nomenclature relating to the computer system: an "account" can mean a lot of things and not necessarily a financial one . Certainly, you can imagine the anger of people who later find out they don't need My TV Pal equipment, and will blame Dish for not telling them so. This Dish policy sounds like a good one, overall.
The CSR said that if an address is used that does not already have a Dish Network account, it will go through the website. But let me stress that Dish is happy to sell any Dish Network customer all the DTV Pal products you want and ship them to the same address as your Dish Network account. Dish just wants to be certain that when you attempt the first purchase that you understand that if you subscribe to LIL's, you don't need the My TV Pal. Once you verbally tell them that you understand this and you want to purchase the products, anyway, they are happy to send the transaction through for you (they probably fill out the same fields that the website has) and fix it so that all future transactions for purchase of any of the My TV Pal boxes--DVR included--will go through the website without having to call Dish.
Again, I think the motive for requiring CSR contact for the first transaction is to offer Dish subs the opportunity to subscribe to LIL's if they currently don't, and to make certain that subs who do get LIL's know that they dont need My TV Pal to be ready for the Digital OTA switch (that saves Dish subs money). However, once you establish that you understand this, they are happy to sell you all the My TV Pal boxes--DVR included--that you want.
So, call the number, talk to the CSR, get your products shipped, and you are all set to make future purchases on the website without interruption. And when you do get your My DTV Pal DVR, please let us know what you think of it. I will most likely purchase one as well because, in my case, I don't want to take up valuable room on my 722 with certain HD OTA locals (the smaller independents and PBS stations that Dish doesn't yet offer in my DMA) that are in space hogging MPEG-2. I would use the My Pal DVR for those recordings and use the 722 for the MPEG-4 LIL's and other channels.