So you are happy because you will be rewarded? In that case, it still sounds strange to me. It's like you have to work and celebrate when work begins, instead of when you get your salary.
I see two ways in which I don't think this lines up with Muslim thinking:
1. They're not happy just because one day they'll be rewarded. Their sins are forgiven. This is a big deal.
2. Islam is not about being rewarded. It's about bringing due glory to Allah. Fasting is a great way to keep oneself thinking about the reason they're fasting. If you're fasting throughout Ramadan, you'd be hard pressed not to think about Ramadan and what it means to you.
At least, this is how I see it from a Christian perspective. I rarely fast, but find that it can be useful for making me more conscious of my relationship with God and the hunger serves as a constant reminder to spend more time in my Bible, pray, and so on.
Jibb
