What Aragorn says above is what I'd say as well - even if they knock money off for taking the wheels off it doesn't make any sense to spend money on wheels you don't actually want or need.
When we were trying to get rid of a stripped Focus recently (and this was really stripped - to the point there was no front subframe on it so couldn't be towed etc) the local scrapyard would pick it up, but it was a case of they wouldn't pay anything for it, and couldn't do it right away and would phone back to arrange. We ended up cutting it up with a reciprocating saw (not recommended as it made a right mess, and not an option with a car with a proper chassis) and lifting it in pieces into a trailer and taking it elsewhere after a week as it was in the way - just as we returned from dumping the first lot off the phone rang with the original place I'd phoned with a collection day arranged!
You may find it helps to remove the brakes and sit the wheels on the hubs directly (remove the caliper and brackets and disc etc) particularly if your trying to fit smaller wheels on there.