Whether or not you guys wanna believe it, paying for a hotel for him is enabling him. I mean c'mon, seriously? This is coming from somebody that got out of rehab a few weeks ago and has 70+ days sober. He has stolen from you guys, walked all over you guys, and treated you like shit and you're going to provide a safe place for him to sit around at use at? Stupidity. Some people NEED to spend some time in jail to realize where their life is headed and that they can only fix what is going on by quitting dope. It isn't easy but this kid obviously will not learn unless he is completely cut off. As for you saying that you didn't want him to steal or whatever, that is just excuses you are making because you love him. It's time to do the whole tough love thing COMPLETELY, because nothing else seems to be working.
and I don't think your dad should be giving him food or rides. if he shows up on your doorstep passed out you can take him to the hospital, but I agree with the majority here and say you guys have got to let him come on his own. It's the only way.
For some insight on the addict's mind, maybe check out Nic Sheff's Tweak. The first 100 pages or so are very accurately an addict at his or her worst.