Unfortunately, they don't realize (as many of the smaller parks have, either intentionally or just due to lack of money to purchase a bunch of new rides to replace ones that they already have) that keeping these types of rides may actually turn out to be beneficial on the financial end as well as from the nostalgia/sentimental viewpoint.
When you are the only park (as was the case here, at least within the US) with this particular ride, you will very likely get some additional people to come to your park just because they want to experience something that is simply not available anywhere else! If you remove that one thing, they no longer have a reason to come to your park (even from a distance, meaning they are likely buying the more expensive tickets not a yearly pass or similar, and probably getting more things like souvenirs that repeat attendees already have), so that is a fair amount of revenue that never arrives.