I have a shop, and we do things like this too.
However, hot food would be a PITA. You will have to pay someone to make it and look after it - your OH needs to be able to concentrate on the punters and the shop floor.
Also, you will get greasy paw prints all over the lovely new stuff. And crumbs.
Giving the something is great though, because it makes people take their time. We tend to give them a glass of something bubbly when they come in (look for special offers at Sainsburys - their cheapest always seems very drinkable. And they do free glass loans) which means they have to stay long enough to drink it, so they look at more things.
We then also have something sweet to offer (posh chocolates, jelly babies, cakes, mini cup cakes, mince pies - we've done it all) but that's far less popular than the booze. We don't bother with fruit juice now as it was rarely asked for, but I suppose it'd be good to have some. We made our own bellinis once - that went well. If you have a kitchen that 'works' you could get a load of peaches and a blender to make them fresh - always more impressive (and no work at all - peach in blender, blend peach, pour into glass, add champagne, plonk in stirrer)
Anyway, in my experience people want a drink and a free hand to look at stuff. They don't want a drink and a paper plate / napkin with food on it because it leaves them with no hands with which to feel the quality :)
Remember to ask everyone to sign up to your mailing list (even if you don't have one yet) - collect their name and email addresses so you can contact them to remind them how lovely you are later. (Use mailchimp - free and lovely)
I've often thought of doing a free continental breakfast buffet on a Sunday morning but we don't have the facilities. Maybe you do if you sell kitchens?
Good luck - let us know how it goes.