YANBU. That was daft of someone to take in a package when they were going away for 2 weeks.
On a slightly different tangent, a few years ago, I posted a package full of gifts (12 in total - worth around £120,) for my brother and his wife and their 2 kids. They only lived 22-23 miles away at the time, but I couldn't tie them down to a date or time to pop in to drop it off. (I didn't want to risk them not being in as it was a long way to go for nothing, and they had no shed or garage to leave it in, and nowhere else to leave it.)
I said I would only stay 10 minutes, as I was quite happy to just drop by briefly and then mosey on into the city (they lived on the outskirts, 5 miles from the city centre.) But SIL kept saying they were too busy for me to pop over.
So I ended up posting the package with ALL their Christmas presents in. I posted it Monday 15th December. The delivery was a 48 hour one and was due between 9am and midday Wednesday the 17th. I texted him to tell him, and he said 'cool. That's great coz Lisa is in all morning.'
I checked on the delivery status at 11am Wednesday, and it said they tried to deliver the package at 10am, and failed, (no reply,) and the package has gone back to the depot. 
I texted my brother to let him know, and he says 'cheers sis! We will get it soon.''
Long story short, they were going away for Christmas on the Sunday the 21st (til Tuesday the 30th,) to stay with her family 100 miles away, and they never bothered going to get the package before they went.
Brother said 'we have been a bit busy packing, we will get it when we get back.' 
So anyway, they never rang the post office and told them, so they tried re-delivering the package on the Monday (the 22nd,) and of course they weren't in!
The package sat in the delivery office til the Friday the 2nd of January, because brother and SIL couldn't make time to pick it up, as life was so 'hectic' after their week away, and then it ended up back with me on the Monday (the 5th of January!) I was so pissed off. 
I asked a few times that week (week commencing 5th January,) if I could pop in to drop it off, and kept getting put off by my SIL. In the end, they popped in when it was my birthday (late February,) and picked the package up then! 
I never ever posted anything to them again.