Animal issues aside, it's a very dated form of entertainment. Frankly, I'm surprised it made it as far as the 1960s.
I'd expect there to be a larger faction of the population who are cool with Tigers and want to see one, but flaming hoops don't light their fire.
I would imagine a pivot to traveling zoo would take major business changes to move away from the stadium experience and towards more of an amusement park or zoo like experience.
Witness the scores of elephant poisonings in Zimbabwe for poaching purposes. If you view people as contradictory to Nature, your efforts on the largest of continents will come to naught.
It's so easy to argue for ideological purity when it doesn't directly affect you or your family (abstract you, for all I know you may live down the road from Kruger). Ultimately though there has to be an incentive for the people affected to part with the resources and opportunity offered by the big animals. Safaris are one (not terribly effective) compromise that at least justifies economically why big animals need to be preserved (no animals means no safaris means a lot less rich visitors).
I also feel that you need some of the natural habitat to remain humanly accessible, in part so that people can experience nature and thus get behind preservation efforts. Creating walled off territory where no one but a few Specially Approved Scientists and deep backpackers can enter does not seem to be the best way to build public support. For portions of land, it may be necessary (hence the wilderness preserve designation in many places) but for much of the land, there is a fine balance between preservation and accessibility.
Safari parks are imperfect but in my opinion fall into this category. Even in the US, the politics of parks can be contentious. (http://www.mnn.com/earth-matters/wilderness-resources/storie...) I can only imagine what a developing country would be like.
That said regarding an earlier comment, I don't view all zoos as 100% horrible these days. A lot are making genuine efforts to try and improve animal welfare as much as possible.