Donny, capos have uses. They are great for acoustic players who need an open bass note in an accompanying setting ("pickin and grinnin").
You will NEVER (or rarely) see a competent lead player using a capo. That generally is the sign of an amateur who simply does not know who to play power chords, or a "picker and grinner" who uses the same basic fingering and a capo to put songs in an appropriate key.
I would bet that the players you see using capos are NOT instrumentalists, but singers who accompany themselves on acoustic guitar. And I'll bet, if you look closely, there is a player on the bandstand doing all the hard parts without a capo.
I have 300 plus guitars and wouldn't be caught dead using a capo...don't even own one, even though I sometimes use one in a studio to use open bass acoustic chords on backing tracks.
I think on the piece I posted last year, I played in 5 or six keys...no capo and probably only one open bass note. But that has as much to do with my style of solo playing than anything else. And, frankly, I choose to play in, say B flat instead of A (one fret down to an open A) because I can (LOL).
Generally, except for the acoustic player needing the open bass note on relatively simple songs, pros just shake their heads and smile when they see a capo.
Russ