I'll provide an example of why a park can be considered an economic development opportunity.
Last year I held a bike race at our local park. it attracted 250 participants and about 150 spectators, mostly from outside my City. Each of these people probably did the following things:
1) Eat at least one meal at a restaurant. Figure $7 each = $3500
2) Filled their cars up. Figure 150 cars at $40 per fill up = $6000
3) Figure 80 rooms at hotels/motels used @ $50 = $4000
4) Supplies I needed for the event (prizes, signs, marking tape etc) = $2000
5) People visiting the local bike shop = $1500
5) Improvement of the image of the city I live in ???
(These figures are pretty accurate, I've travelled enough with bike races and been to enough to have a pretty good idea of peoples spending habits)
So for a one day event, with very little sponsorship I generated about $17 000 in economic spin off. Now figure what a provincial park, like Alconquin(sp) or even small conservation areas (Hilton Falls) puts into the local economy on a daily basis.