I can see advertisements in Stack Overflow. But I can not see any advertisement in Meta Stack Overflow. As per FAQ for Reduced advertising I need 200 reputation for that. But I have less than 200 reputation. But I can not see advertisements here.
The "reduced ads" privilege on Meta Stack Overflow requires one rep point. In other words, there are no ads on Meta.
Admittedly, the privileges page here says that you need 200 rep for reduced ads. That's because it's true for the other sites on the network, and the MSO privileges page is a wiki that gets copied to every site.
In other words, there is no bug, it's just bad documentation that's caused by the way the privileges page is set up.
There are no ads on Meta.SO, like there are no ads on all SE 2.0 sites.
The only sites with ads are SO, SF and SU.