The Federation has an excessive amount of clean, renewable energy sources, they produce so much energy and use it so efficiently that they don't know where to put it. And then they mastered the technology of turning energy into matter and vice versa.
This would work only if the federation knows how to break conservation of energy (it doesn't, as per the entirety of star trek).
You seem to have no idea how much energy is needed in order to create, for example, 1 kg of atoms.
This would be the energy produced by +1/2 kg antimatter and +1/2 kg matter (assuming the federation can efficiently capture and use neutrinos). In other words, enough to atomically blow up an entire continent (easily).
The energy generators shown in star trek (matter/antimatter and fusion generators) are not powerful enough - by orders of magnitude - in order for energy so wastefully used to be plentiful.
Well, apparently they are, because they do all that stuff on a regular basis, don't they?
No, they don't - I hope you do realize it's only smoke and mirrors, yes?
If you want to come up with a non-absurd/hillarious explanation, well, that's not the 'converting matter into energy' one - assuming you want to maintain even the pretense of following the laws of psysics.
A more credible explanation (offered and consistently used in trek lit) is that replicators use already available matter and rearrange it into the needed combinations by using acceptable amounts of energy.
Read - available matter; energy. Someone has to get them.
Also - job as a waiter, miner, etc, etc - if you think a substantial percentage of the population will do such jobs day in and day out only because of 'hobby' -
ANY job involving stress, repetition, responsibility (as in - if you make a mistake, say goodbye to your career, social status) and less time with family/friends requires incentive beyond 'hobby' in the medium and long term.