I'm sure they would :D
I have found this recently.. can be fed starting around 8 weeks - just a thumb size one will last a while.. it can stay in the tank for 24 hrs and not foul up the water, allowing the fry to munch all day as they please. I am considering getting some at some point to try out.
Halfway down there are pictures with links to the different types - the meat pie would be the best for the bettas :)
Unsure if you have heard of it or not - but may come in handy for those days you do work and can't feed as often.