Well, this is partly why we end up with so many.. People approach me often at work and in the neighborhood saying, "We figure you'll help..." Meaning take our cat, our stray that we've been feeding, our colony that we can't stand anymore because it's breaking us financially and they keep breeding..." But noone (rarely someone will offer a little money) wants to sponsor them!
Just last week, my neighbor asked me to get her a discount on a nueter for a stray that she's keeping but she can't take the trip so would I do all the transportation during my work day (way out the way!). Well, you are a gem for taking on this gal and hopefully can find her a home! We do what we have to do! You may want to post a lost ad in the newspaper just to make the owners feel a bit guilty- could say "will have to release to shelter" in a vague way saying they should think twice, but then again, no, best left alone...better they drop off at your house than a bunch of other places (like in the woods like they do here)! Keep us posted and good luck and thank you!