It particularly makes no sense when megachurches are independent
But it makes no sense to criticize the megachurch based on its leadership since they are all independent.
No they're not, they are in fact usually part of what can best be described as a "Worldwide Religious Union" called The Assemblies of God:
As such they really are NOT independent churches despite giving the appearance of being independant(and their legal independance). For example the leader of the Assemblies of God in Australia is Senior Pastor Brian Houston.... who also happens to be the leader of arguebally the southern hemisphere's biggest and the most internationally famous "megachurch", the Hillsong Church based out of Sydney's Acer Arena!
Those that are not part of the "Assemblies of God" are usually just too "small", but are usually basing their church around the general Assemblies of God style and are usually affiliated in some way anyway.
The Assemblies of God frankly has ruined Pentacostalism in my opinion. There was once a time when Pentacostal Churches mirrored much Catholic beliefs. Such as in the early days of Azuza Street when they had such a beautiful independance and uniqueness about their "raw worship", communion services around the clock(it was a 24 hour church, 7 days a week!), taking Christ's commandments on communion 100% literally(to the point of having it offered every few hours, including overnight... talk about "as often as you do this"...), confessions/repentance(Public and private!) by people who just walked in off the street at any hour they wished to(once again the church was open 24 hours, so naturally this "confession" ministry was avalible 24 hours, 7 days a week)... Alot of it sounds very Catholic like to me.
Thanks to the way things have gone in pentacostalism(it drifted towards anti-catholicism, most churches only do communion services once a month, 24 hours 7 days a week now down to a few hours on a Sunday morning, there's now commonly 1.5-2 hour sermons by Pastors, Confession? what confession?,), all of that is a thing of the past and I believe it's mostly the "fault" of the AOG organisation that oversees most pentacostal churches.
Azuza street should be as much of an inspiration to Catholics as it was to the early pentacostal movement. It must have been a very energetic and vibrant place, and from what I know it's the only 24/7 Church I've ever heard of!