Yup, there is a $29.99 HD only package.
Whoever told you there wasn't didn't know what he was talking about.
Although I am not sure you are able to subscribe to that if you lease the 622, since I think it's required that you subscribe to one of the DishHD packages(bronze or higher) if you are leasing the 622.
If you purchase the 622, you'll be able to subscribe to the HD only package.
Note: If you got the reciever for $299(or $349) then you are leasing it, and will have to return it to Dish Network if you do not sign up with them. If you do not return it, your credit card will be charged for the price of the reciever.