My experience in Chicagoland is quite the opposite. (Is Chicago like other areas?) Each local Catholic parish has extremely narrow demographics. As My wife and I frequently moved, we visited many Catholic churches and were told bluntly that we did not belong in that church. Then another parish was named as the right church for our demographic group. We were always sent to a parish at the lower end or our mixed marriage.
Because small evangelical denominations do not have a large number of churches close by, their congregation of 100 has more diversity than a Catholic parish of 5,000.
In 1964 I did a research paper on upward mobility of people in the inner city. The research discovered that the church was the major vehicle for upward mobility. Evangelicals had more upward mobility than Catholics. In the Catholic church, only activity in a regional Knights of Columbus or similar group provided a vehicle for upward mobility. But these groups attracted few young adults so they did not provide a vehicle when it counted.
But small evangelical denominations had strong ties between churches in poor, middle class and wealthy areas. Joint meetings were frequent. An unemployed person would openly pray for a job, or a better job because his wife was expecting. The pastor/evangelist would openly pray the same for him, lay on hands, etc. In the congregation would be a supervisor, foreman, union steward or senior employee who knew of an opening at his place of work. Miracle of miracles. God answered the prayer. Read Horatio Alger again. Thats it!
Moving from the area of the poor church to the area of the middle class church was the next step. I have closely followed housing and housing choices. Ask any nominal Catholic who only attends on Christmas, Easter and his nephew's baptism where he moved to. More than any other answer, he will name the parish he moved to, not the village. (The public school also gets frequent mention.)
There is a climb from pentecostal/Assembly of God to Baptist; to Evangelical Free; to non-evangelical mainstream Methodist or Presbyterian and then to secular. The climb may take generations.
For Hispanic Catholics, the climb is from Catholic to Pentecostal to Baptist and back to Catholic. My parish had a discussion in Spanish about Priests and sex abuse. The attitude gap was startling.
The white upper class Catholics who minister to the Hispanics described the problem in the psychobabble of illness and treatment. The Hispanic Catholics talked of sin; good and evil; right and wrong. The Hispanics were concerned that many Catholic Hispanics would switch to Pentecostal/Assembly of God due to the scandal.
The whites were concerned the scandal would be a setback to the reforms of Vatican II. These white Catholics do not want to associate with lower class Pentecostals and Baptists. They favor of Ecumenicism and Unity ...but only with upper class Methodist, Presbyterian, UCC and Universalist churches.
A few years ago, when my wife finally found this Catholic church that accepted our mixed marriage I converted to Catholicism, which for me is like changing from Baptist to Evangelical Free. During the confirmation process they refused to recognize my fundamentalist baptism. They would welcome a Universalist or Christian Scientist equivalence, but not a fundamentalist Chritian Missionary Alliance. But their ecumenicism insisted there be only 1 baptism. Catch 22: I could not be baptized again. The result was they winked (literally, they squinted one eye) and gave me a provisional baptism that was only a baptism if my fundamentalist baptism was not a baptism. But if my fundamentalist baptism was a baptism, then this Catholic baptism I had never happened.
And you wonder why some of us are confused?
Sounds a little like this exchange:
Mark
11:28 And say unto him, By what authority doest thou these things? and who gave thee this authority to do these things?
11:29 And Jesus answered and said unto them, I will also ask of you one question, and answer me, and I will tell you by what authority I do these things.
11:30 The baptism of John, was it from heaven, or of men? answer me.
11:31 And they reasoned with themselves, saying, If we shall say, From heaven; he will say, Why then did ye not believe him?
11:32 But if we shall say, Of men; they feared the people: for all men counted John, that he was a prophet indeed.
11:33 And they answered and said unto Jesus, We cannot tell. And Jesus answering saith unto them, Neither do I tell you by what authority I do these things.