A couple of things:
The ads are not louder. By regulation they are not allowed to be. They are simply dynamically compressed into a very small volume range (near the maximum (loud) range) so that they appear to be louder. The programming itself has a much larger dynamic range (from loud to soft), therefore it appears to be less loud even though the loudest parts of the programming can be as loud as the commercial.
The volume regulation on most TVs, etc. equalizes the volume of the incoming signal for various sources, or perhaps even for various channels, however, it can do little for dynamic range variation - like commercials.
If the TV or AVR has a "midnight mode" or similar dynamic compression technology, then there is usually not as much of a difference between the programmes or the commercials because the dynamic range of the programming is narrowed.
Any mechanism to change or combat this dynamic range takes away from the intent of the programming, so audio purists may not appreciate this "tampering" with the signal, although some people may prefer it.
I haven't watched commercials since the mid-1970's, so this hasn't been an issue for me for a long time - VCRs then PVR. My time is too valuable to spend it watching commercials. Even if you pay yourself only minimum wage, the payback of a PVR is under a year, not to mention all the other benefits of owning a PVR like watching on your own schedule, etc.