yeah I thought it was spy-ware too at first... clicking the "what is this" in the pop-up lets you know that it isn't though
It's the decision of the admins one way or another so I'm not going to bitch a moan and complain simply voice my opinion as a member:
I personally don't like this form of advertising and I've always enjoyed the fact that XS didn't use it. I feel there are many other ways that are just as lucrative, if not more so, that could generate revenue without intruding on the members experience. A good example is web-comics; most of them generate revenue through paraphernalia such as a variety of t-shirts, hats, stickers etc. or a simple Donation box could help as well. I know I would buy a few collared or polo XS shirts for work, or give a donation every so often. Heck you could even hold a contest where people submit designs for T-shirts and desktop background etc. to aid in the creation of these things. Another idea would be to autograph reviewed products and put them on Ebay
These are things I'm sure a lot of members here would be more than happy to do, not to mention you're giving them a choice (unlike a membership fee).
If all else fails just ask the members for ideas... you have a brain-trust of 200000+ people.... I'm sure you'd get something good out of it.
Another idea would be paid vendor pages where people who do a lot of business in the BST could pay a small monthly fee and get a single page on the XS servers to sell their products.