So, what is exactly replicator then?
Basically, it's a very creative transporter.
But even if Replicator could transform energy into a materialized form (food, weapon, etc), there should be several type of replicators. I think that the government would limit the capability of household level replicator. Or else, a crazy man would replicate nuclear weapon and destroy his neighborhood.
Actually, the limitations are probably more fundamental than that. With the base material used by replicators, there'd be a pretty limited range of substances you could replicate, and most of those would be edible. This seems to be the case even with industrial replicators, hence we've seen terrorists go to somewhat extraordinary lengths to obtain random devices and substances (Tahna Los almost getting his ass shot off to steal an antimatter converter and later buying bilitrium from the Klingons) in order to physically assemble weapons of mass destruction. Clearly Tahna's smart enough and motivated enough to hack a replicator somewhere to remove its safety protocols (because EVERYONE in the 24th century apparently possesses advanced hacking skills) so it's probably more of a physical limitation than a regulatory one.
Household Replicator could only replicate food
Public Replicator could replicate household items and everyday need
for more important tools or spare part, you'll need industrial replicator
Very true, but even then the limits are based more on the matter source than any artificial limit. This would also imply there are certain food items replicators simply cannot make because they require substances that aren't in the edible/household matter stock.
An interesting question for our encyclopedic fans: how often have we seen replicators being used to make metallic objects? I can only recall this happening once, when Chakotay used it to make a watch for Janeway's birthday.