Oh yes there are congregational differences and yet many R&F bottom tier Witnesses think it is impossible and utterly untrue.
There are classes in our society that reflect most other societies.
1 lower class-
average R&F who spend their lives in blind faith toiling for converts in their territories, living for the utterances of the WT. This group perplexes me the most even though I have lived among them for 28 of my 34 years. With other levels it is simple motivation to climb a ladder & understanding the "game". But these, these seem to check their brains at the door and give much for little to nothing in return. A few go-getters climb up the ladder to become small time power trippers or ExJWs. Thankfully due to the information age many are 'waking' up from this WT induced trance.
2. middle class-
Better educated, donating high enough amounts to receive special attention. All children are expected to both attend college & do some time at Bethel, MTS, Gilead...etc. Then to go off into the world as esteemed members who ulimately trade their time/trade skill for status and 'privileges'. Most of these congregations are extremely liberal & DFing is rare since everybody is morally guilty of something. Free Speech is what I miss the most. I was never taught the WTS was infalliable nor the words of the WT liken to Jah himself speaking. Most of the WT topics were considered as 'suggestion' if they went beyond the Bible. They aren't taught to be 100% so falling short of WT literature standards are not a blip on their radar. You learn to be model JWs at the Hall or JW events much like you learn to dress to impress for a job interview.......Their FS times are often fudged & treated as mini excursions. Knock on 2 streets then off too the (insert recreational location). These have higher numbers of born/raised JWs then converts. On another interesting note...many have/had live music in the KH or have some sort of JW bands on the side.......The R&F will insist a person is 'crazy' to say such KHs exist but of course they do but are less in number then the lower class.
3 upper class -
These are those who choose to stay in the WT Corporation mainframe as a "career" & acheive a level of 'authority & influence'.
4 Stockholders-
I personally don't know how many there are but I know they hold a meeting privately every October. "The secret society" of the Watchtower. Like all secret societies their deeds are only limited to our imagination.
Just my observation.......