Well, I actually feel there are two different issues here.
I think the original post is more a question of diminishing returns and finding a point with markers where by more money put into a purchase does not equal more performance coming out. I posted about this over a year ago when I was originally getting into torunament play and got a similar response.
Since then I have owned most of the high end guns and I do believe there is a point where by you are paying substantially more for no increase in raw performance, or certainly nothing worth the extra 200-300 pounds/dollars you will be paying.
I think once you get above a marker than can achieve 15-20BPS with some form of anti chop system there is no massive performance gain to be had for spening masses of extra money.
For example, if you bought a Vision Impulse for £400 then I don't think a £900 Angel A4 is more than twice the marker in terms of flat out performance (e.g. balls being fed from your hopper and sent down the barrel).
With the Impulse example you are going past a point of diminishing returns. E.g. paying greater amounts of money for increasingly miniscule performance gain.
However, this then brings us onto the second point. I don't own a gun physically capable of 15-20BPS, I have one capable of 25-30BPS. Can I shoot that fast? No. Do I care? No!
I want me to be the limiting factor, not my equipment.
I really don't feel that paintball is any more expensive than any other top end hobbie.
Golf, per annum costs about the same, so does premiership football spectating, going on the piss every weekend, smoking legal and illegal substances etc etc etc
Everybody moans about the cost of kit but you can go in almost any half decent high street shop and pay £40 for a wooly jumper! And a Dye playing top is expensive???? Pair of Jeans from River Island/Next are about £40 and they will wear out in a couple of months. Pair of JT tournie pants = £50 and I'ver played in them all last year (even went up Snowden in them!!!). So is Paintball kit expensive? Really?