I do a bit of work for rescues, mostly lurcher and greyhounds and yes, some rescues will take against you if you are someone that works thier dogs. It depends where you go, PM me and I can give you the details of some sites if you like.
The main rescue I help will rehome to working homes, if it suits the dog but she mostly deals with track greyhounds. I did foster a lovely little beddiexwhippet for her recently that went off to a working home and now spends his days rabbiting!
I take my hat off to those heavily involved in rescue, they see some harrowing sights, day in, day out brough