There are 2 aspects to this Sandra. The scone will give you a spike in all likelihoods, but you can argue "would an occasional spike harm me"? The answer is probably no. HOWEVER, this is a bit like a smoker trying to give up and saying "would the occasional fag harm me"? Probably not, but one fag becomes 2 and so on.
I think that as diabetics, we need to think like smokers and alcoholics - AVOID the things we like that we know are bad at all costs. Carb addiction is as bad as any other. It's a bit different for people on insulin. One of the only advantages they have is that they can inject to allow for such treats. You can't. Not that I envy insulin-takers.
I try to think like someone with a nut allergy. They aren't allowed to weaken and have an "occasional peanut butter sandwich"
For snacks, I eat a lot of snacks. I have one apple every day. i have one satsuma every day. Sometimes I have some strawberries or raspberries. I OCCASIONALLY allow myself one or two small squares of chocolate - suprisingly, quite low GI. I do this as a reward if I do a lot of exercise. I occasionally have an Atkins daybreak bar. Even if you ignore the "net carbs" hype it's still only about 8 grams carbs for the bar max, and low GI. They never move my BG. Some say the polyols (which are used to replace the sugar) can give you tummy upsets, but I think probably only if eaten in large quantities. never affect me like that, and they are nice. A cold hard boiled egg is a nice snack. As is a few prawns or cockles - do you get cockles? Small clams, often pickled. If I'm out, and in a cafe, I normally just moan and say no, or have a bag of nuts, or my own treat I've bought with me (tell the cafe owner it's for diabetes, they never moan. Too scared to)