If that is a problem, it is a problem for those advocating these policies. If you selflessly advocate policies benefiting the wealthy, low and behold, many of those seeking to benefit will appear. If these types generate corruption or exploitation, how do you filter them out?
In general, a lot of low-regulation, low-tax advocates claim that selfishness isn't a problem, that these approaches can benefit everyone even when everyone looks out for themselves.
The problem with such approach is they don't consider that those attracted to these approaches for selfish reasons aren't going to be satisfied with simply an efficient, meritocratic system that turns selfishness to a universal benefit and that instead the truly selfish cheat, take any resource they can get access to and essentially spoil many idealized "general benefit through individual benefit" systems, turning them into just "the strong prey on the weak" approaches.
And those on the sidelines looking at the situation can say, "Oh, looks a few people actually believed this stuff, too bad for them that the overall process was swamped by those just aiming for a buck." But this situation doesn't raise our overall admiration for any of them.