Theresa, that could well be the case. I now have lots of SB bonds (the card encourages frequent purchases) with some worth as little as 50 euro. I have often thought that having lots of low value state savings accounts is inefficient from NTMAs point of view - lots of post, admin, forms, freepost envelopes for reinvestment for small amounts etc.
Also, I have 100k worth of prize bonds so win regularly (50 quid prizes which I put into SBs) and chose the option of getting a cheque. Every cheque comes with paper, a brochure etc.
I'm not sure what is happening with my annual SB interest - can't remember what I wrote on the form originally or what the arrangement is. I think it is going into an account but will have to look into how to get at it.