She pays annually and her year is up in May.
The lease fee on the first receiver on the account is covered in the cost of the basic programming package. The problem for your Mom is that she pays annually. Annual pricing is discounted (roughly one month free) and therefore doesn't cover the lease fee.
I don't know what they offer in terms of annual pricing anymore, since it isn't even mentioned anywhere on their website that I can see. But, I can tell you about two of the packages that I am familiar with. My year was up this week and I just made a change. I too was paying a lease fee that couldn't be explained. I talked to several CSRs that couldn't explain it. When I called to change packages I brought it up again and finally got the explanation, it was because of the annual package discount.
Classic Silver 200 is $47.99/month or $528 annually. So if you pay annually, that would be the equivalent of $44 per month, a savings of $3.99 per month over the regular price.
Classic Gold 250 is $57.99/month or $638 annually. So if you pay annually, that would be the equivalent of $53.16 per month, a savings of $4.83 per month over the regular price.
So she is spending $7 to save $4 or $5 dollars. Not only that, but annual pricing is not a qualifying package to get local channels for $5 per month, instead it is $5.99 per month.
So by switching to monthly, she could actually save $3 to $4 per month (more if her state charges taxes).
At one time, paying annually made sense, if you were a satisfied customer that planned to be around for a while. Now, it seems there would be very few cases where it would be an advantage to the customer.