[llimos]

That is not really true of most Orthodox Jews. Keeping the laws is about following the word of God, and the afterlife does play a fairly big part in our worldview. There are a handful of laws which are identified in the literature as being about community but those tend to be ones added later by the early rabbis (miderabannan), rather than straight from the Torah i.e. God (mideoraisa).

That being said, what you described in your second paragraph does happen, yes. Though not everyone who engages in it has the motives you ascribe to them. Some are sincerely trying to do the will of God as best they can.

> It's not a sin to fail to keep kosher

Well, it is for a Jew, but not for a non-Jew. We don't say that non-Jews need to keep our laws, other than a few very very basic ones likes not to murder. Non-Jews can still have an afterlife without keeping kosher.