In the article, Kevin said "Consider the scenario that if I dig a lake in my own very private back garden, I legally have to purchase a Rod Licence to fish in it, why?"
The simple answer is because of the requirements set out in the Salmon & Freshwater Fisheries Act 1975. The legislation is there to protect fish (from anglers and other people that exploit them), it's not about raising revenue for funding sport.
I spent a few years working with councils trying to persuade them of the benefits of investing into angling infrastructure. Part of the problem though is that the general public is not very good at managing angling facilities. Most well-maintained fisheries are in private ownership (fishing clubs, or commercial fisheries).
It is a complex issue, and I do not believe that you can draw straight parallels between angling and any other 'sport'. I'll try to explain... if you find any town that has enough residents, and build a football pitch, then people will be able to come and play football. The blueprint for a football pitch looks pretty much the same no matter where you go in the country. Same goes for a basketball court, tennis club, rowing course, martial arts studio, etc etc. Sports projects are generally easy to replicate.
However, there are many disciplines to angling, and an infinite number of types of fishery, habitat, stock composition and density, etc. That is why statistics in angling are very misleading. If you build a 'coarse match lake', then it's unlikely to appeal to fly fishermen, or specimen barbel anglers. Identify a quality public-owned salmon river beat, and not many carp anglers will be interested.
There is a further problem in that angling is greatly influenced by external 'environmental' factors. You dont tend to get issues with cormorants, otters, zebra mussels, blue-green algae, KHV or signal crayfish at a football pitch.
Compound that lot with the fact that anglers can rarely agree on anything (plenty of evidence on this site of that!) and we gradually become a difficult market to understand and cater for.
Other sports can access funding because their 'product' is easily identifiable. Invest in football pitches, and you'll get more grass roots clubs, more participation, healthier kids and maybe a knock-on effect that one of your new recruits might one day play centre-half for his country. The TV and sponsorship money at the top always trickles down and at least there's a chance it is put to good use.
Invest in a public-owned fishing lake, and the only thing I can guarantee is that you'll get a myriad of opinions about what different fish should be stocked and what the rules should be made, a pipeline full of potential environmental 'issues' that can put the whole investment in jeopardy, and not many professional people stepping forward to manage any of these problems. If you find a successful angling 'project', then every time there is a small number (often just 1) of very dedicated people, making hardly any money, at the centre of it. Doesnt sound much like football to me. How much is Carlos Tevez getting paid again?
Dont get me wrong, I think angling is a wonderful thing, be it a sport, a pass-time, an engagement tool, or a vehicle for education and well-being. It had great depth and complexity, and is worthy of far more than being labelled as just another 'sport'.