The way it works is this:
When a page loads, ads load on the page. We are generally paid for ad impressions (and rarely for ad clicks). Every ad loaded on a page gives us a tiny bit of money.
Ad revenue is one of the most significant sources of income for the site and is used to fund development, infrastructure and support costs. The site is NOT cheap to run.
we have to either rely on users subscribing, or letting the ads load on the page. The ads are the least aggressive way we can support the site. THey let us provide free downloads and content to a lot of people. If we didn't have the ads, or if more and more people blocked the ads, we'd have to think about what we could continue to give away for free.
I personally select the ad formats and placement on the site, and am the one who works with our ad services to determine what types of ads get placed on WinCustomize. There are no pop-ups, pop-unders, slide-out trays or anything else that actually gets in the way of navigating the site. Believe me, I hate annoying ads as much as anyone else, but at the same time I have to place them on the site to keep the lights turned on.
I ask that you not block the ads on this site (unless you're a subscriber, in which case you see none anyway), as it's those ads that let us provide the site to you. There's no such thing as "free" when it comes to sites like this. We need the revenue to keep operating. If the site provides a service that you find useful, all we ask is that you let the ads load. Ignore them, don't bother clicking on them, just let them load. It's a passive act that helps us immesurably.