Hi -- I'm not sure about this. I just tried one of your items (I took the risk of hitting the "BIN" button), and was taken to the usual "Commit to Buy" screen.
I think this depends what site you're buying on and what the sellers are specifying. You may be running into sellers on .ca who have items set up with Immediate Payment Required (IPR). With IPR, you'll be taken directly to a screen that leads to checkout.
On the other hand however, on .com apparently IPR is the rule now. Today at the Wed. board hour Raphael mentioned that on the .com site, all items under $100 are now IPR. Were you buying on the .com site? If so, this may be what you were encountering.
You're right that this does make it a lot less convenient to make mixed purchases of BIN and auction items. It used to be you could use BIN/Commit to Buy to make the regular purchases, then wait for the auction(s) you were bidding on to end before paying. At least on .com, for items under $100, that's no longer possible.
I imagine eBay.com is trying to reduce UIDs/non-payers, but it will have the effect of discouraging mixed auction/BIN multiple purchases, as you say. In my view, things are continuing to evolve on eBay in the direction of assisting the biggest commercial retailers in automating and streamlining their selling. I doubt many of them offer auctions.
