43/45 seconds is rather obscene, but it doesn't seem to be actually related to the ad's - I just did the same test in about 10 seconds.

Wasn't the ads at the top of each page enough to keep the lights on?
They were, but unfortunately that couldn't last forever... advertising revenues (for the entire web) keep on going down over time, and presumably costs (such as staff etc) keep on going up too.

At least we are only getting to this stage now, many other sites have been like it for several years.