The regulation requiring this reserve on takeoff exists to make you
think about whether you actually have enough reserve fuel for your
flight. You've done this, so mission accomplished.

The rule is quite minimalist - only under the best of circumstances is
a 30 minute reserve sufficient. This is a good thing - it allows you
to go with that minimum when there is an advantage to doing so and the
circumstances allow it. It also means that the minimum isn't always
enough, maybe because you encounter unexpected headwinds or weather you
have to divert around. No big deal if airports are 5 minutes apart
where you are, but a much bigger deal if you are out over the Gulf of
Mexico. My personal minimum for overwater flights is 2 hours fuel when
I reach land, day or night, VFR or IFR. On the other hand, I consider
a reserve of 30 minutes at 45% cruise power just fine if I'm making a
day-VFR hop in good weather to an airport with multiple runways and
multiple airports within 15 minutes flying time. I'm glad the rule is
minimal enough to allow me to make my own decisions.

Air carriers have much more complex rules about fuel reserves. It's a
form of micromanagement, in a way - the rules are far more complex, far
more restrictive - and in spite of accurate fuel gauges and fuel
totalizers, lots of experience, better training, etc - airliners still
manage to run out of fuel.

Michael