My DS is also a very chucky baby and i sympathise with all the washing. He is still going strong with the spew and im hoping it stops soon! I dont let him sleep in his bib as I personally feel it is a bit of a risk. Something that has worked for us is one of those wedges that you put under the sheet in the cot. It elevates ds head so he isn't sleeping flat and since we started using this we have found a reduction in the spew in bed. Also if you are concerend about the cost of gro bags you can get cheaper versions in target etc. We got a nice one from pumpkin patch which ds uses which was around $30 i think.

Good luck with the washing